Following are comments on Friday by policymakers attending the Group of 20 Summit in Cannes, France, and other euro zone officials, as Europe considered the possibility of Greece leaving the euro.

PRESIDENT BARACK OBAMA

The world faces challenges that put our global economic recovery at risk.

Events in Greece over the past 24 hours have underscored the importance of implementing the (euro zone crisis) plan.

I am confident Europe has the capacity to meet this challenge. What the world looks for in moments such as this is action.

Our European partners have laid a foundation on which to build and it has all the elements for success.

Here in Cannes we've moved the ball forward.

All of us have an enormous interest in Europe's success and all of us will be affected if Europe is not growing.

I think the Europeans agree with us that it is important to send a clear signal that the European project is alive and well... They are the first ones to say this begins with them arriving at a common course of action... We've seen all the elements for dealing with the crisis put in place.

Based on my conversations with Sarkozy, Merkel and other European leaders, I believe they have (a) strong commitment to the euro.

Greece continuing with reforms and structural change, that's the right recipe, it just has to be carried out.

European leaders understand that what the markets are looking for is a strong signal that they are standing behind the euro.

I think there'll be some ups and downs along the way, but I am confident the key players in Europe understand how much of a stake they have in making sure this is resolved, that the euro zone remains intact.

Let's recognize how difficult this is. I have sympathy for my European counterparts. We saw how difficult it was to save the financial system back in the United States.

There's a silver lining in this whole process -- it's that I think European leaders recognize there are some structural reforms they need to make if Europe and the euro zone is to be as effective as they want it to be.

There are just a lot of institutions here in Europe and I'm not sure whether it was Sarkozy or Merkel or Barroso or somebody here, they joked with me that I'd done a crash course in European politics over the last several days, and there are a lot of meetings here in Europe as well, so having to coordinate all those different interests is laborious, but I think they're going to get there.

IMF MANAGING DIRECTOR CHRISTINE LAGARDE

On the IMF's role in the European bailout fund: The IMF lends to countries not to legal entities, so the IMF would not lend to the EFSF (bailout fund), it would not join in the EFSF.

If the EFSF is called on to intervene in a particular country, the IMF can partner with the EFSF on the particular venture.

On monitoring the Italian economy: The problem that is at stake, and that was clearly identified both by the Italian authorities and by its partners, is a lack of credibility of the measures that were announced. Therefore, to attest the credibility of those measures -- in other words their implementation -- the typical instrument we would use is a precautionary credit line. Italy does not need the funding associated with it so the next best instrument is fiscal monitoring.

On timeline of IMF mission: I expect that we can be on the ground and running before the end of the month.

On Greece: We expect the current and unfolding and hope completion of the political crisis to restore sufficient clarity so we can continue the relationship on a normal standing.

On IMF resources: I go away from Cannes with an unlimited 'no cap, no floor, no ceiling' on resources. The members are saying we will do whatever it takes in terms of resources so that the IMF is fully equipped in case of crisis.

I take that as a reaffirmation of the role of the IMF in case of crisis. I know some would have liked to see big numbers...(but) under present circumstances, given the degree of uncertainty and the degree of uncertainty, it is not bad to not have a limitation and to have a unanimous commitment that resources will be available.

GERMAN CHANCELLOR ANGELA MERKEL

There are hardly any countries here which said they were ready to go along with the EFSF (euro zone rescue fund).

FRENCH PRESIDENT NICOLAS SARKOZY

We never wanted to change governments, either in Greece or in Italy. That is not our role, that is not our idea of democracy, but it's clear that there are rules in Europe and if you exonerate yourself from these rules you exclude yourself from Europe.

Italy has a council president whose name is Silvio Berlusconi, who put forward a plan. This is a reality that has come before us by democratic means. And Silvio Berlusconi, who is aware of market doubts over the implementation of the plan, has asked the commission and the IMF for monitoring.

Why would you want us to set the conditions for bringing in one government or another in a given country? That would be madness.

On growth: We have decided to use all the means at our disposal to support growth. The situation is much more complex than in 2009. There is no single response. Washington and London were about all out measures to support growth. Toronto was about reducing (debt) by any means and Cannes is about differentiating situations according to the country.

We consider it morally indispensable that people of the world know that financial players who have led the world into the troubles that we know will have to contribute financially to the damage which has been done.

BRITISH PRIME MINISTER DAVID CAMERON

Every day that the euro zone crisis continues is a day that has a chilling effect on the rest of the world economy.

Britain will not contribute to the euro zone bailout fund and we are clear that the IMF will not contribute to the euro bailout fund either.

Global action cannot be a substitute for concerted action by the euro zone to stand behind their currency.

The very worst thing would be to try and cook up a number without being very specific about who was contributing what.

The job of the IMF is to help countries in distress, not to support currency unions.

The world can't wait for the euro zone to through endless questions and changes about this.

You can't ask the IMF, nor should you, nor ever would I, ask the IMF to put its money into a euro zone bail out fund - that wouldn't be right.

Britain will not invest in a euro zone bailout fund. Britain will not invest in the IMF, so the IMF can invest in a euro zone bailout fund. That is not going to happen.

If you go back to our last increase in IMF resources, there was a parliamentary vote. That vote allowed for some extra headroom and what we'd anticipate doing would be within that headroom.

SENIOR U.S. OFFICIAL

The G20 statement will see some pretty strong language, stronger than we had before... recognizing China's determination to move more quickly to a more flexible exchange rate system.

Growth looks more resilient than many of us thought it would be. However, growth in the United States and growth around the world is too slow.

BRITISH FINANCE MINISTER GEORGE OSBORNE

I don't think anyone should underestimate that a Greek exit from the euro would be pretty traumatic with all sorts of consequences and indeed some of those consequences frankly are unpredictable at this point.

So I don't think anyone should think of that as the easy option. The better option at the moment is for Greece to implement what it agreed to implement most recently in the deal struck by European leaders last week. Now obviously the situation in Greece and Greek politics is very, very fluid -- to put it mildly -- and we will see what comes out of Athens today and we will see how Greece handles its responsibilities over the next few weeks.

What we can do as people who aren't in the euro but obviously have a huge national interest in a more stable euro is help them face up to those responsibilities and at the same time shoulder our responsibilities as part of the international community to have a more stable international environment.

On the IMF: Alongside our other international partners -- like the Americans, like the Japanese and Chinese and others --we have to make sure the international institutions of the world, like the IMF which helps countries across the globe, are ready to withstand global shocks.

It potentially means an increase in resources for the IMF, not just from Britain but from many, many other countries.

We don't have specific figures here because they are part of a negotiation.

AUSTRALIAN PRIME MINISTER JULIA GILLARD

This meeting brought Greece back from the brink. The uncertainty surrounding Greece has been reversed and strong steps have been taken to bring Italy back on track.

Europe needs to get its own house in order, but the rest of the world has a role to play in shoring up the financial system.

We need to find a way forward on trade. There was recognition that consensus on Doha is eluding us and that we need to find a way to move forward and an agreement that retreating to closed markets is not an answer to the challenges we face and (there was ) an agreement to take a fresh approach to move Doha forward by breaking it into manageable goals.

EUROPEAN COUNCIL PRESIDENT HERMAN VAN ROMPUY

We (euro zone leaders) wanted more lending capacity, more resources, available for the International Monetary Fund.

And... we have ...different options and I mentioned them in my introduction. We asked at the G20 level that the ministers of finance of the G20 work on the establishment of those three options.

One of the options is to set up, you can call it some kind of trust fund, enhancing the resources of the IMF. So this is not only meant for the euro zone, it is meant for the global community.

CHINESE PRESIDENT HU JINTAO

On Thursday: At this critical moment, the G20 must work to address the key problems, boost market confidence, defuse risks and meet challenges, and promote global economic growth and financial stability.

We should speed up the adjustment of our respective economic structures and endeavor to achieve fairly balanced growth of the global economy. To keep asking emerging markets to revalue their currencies and reduce exports will not lead to balanced growth. On the contrary, it would only plunge the global economy into a 'balanced recession' and make sustainable growth impossible.

We should advance the reform of the international monetary system in a steady manner, expand the use of the SDR of the IMF, reform the SDR currency basket, and build an international reserve currency system with stable value, rule-based issuance and manageable supply.

(Reporting by Laura MacInnis, Alister Bull, Tetsushi Kajimoto, Gui Qing Koh, Luke Baker, Daniel Flynn, Alexei Anishchuk and Catherine Bremer; Editing by Nick Vinocur)

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