U.S. Secretary of State Hillary Clinton urged India on Friday to join Washington in supporting Pakistan's fight against terrorism, but Delhi demanded results before it begins formal peace talks with its rival.

Clinton is due to arrive in Mumbai late on Friday to start a five-day visit designed to cement ties and dispel any doubts about U.S. President Barack Obama's commitment to India's role as a rising global power.

Although her trip has a wide agenda, including securing a deal to ensure U.S. arms technology does not leak to third countries, Clinton is expected to push for a smoothing of Indo-Pakistani ties frayed by last year's Mumbai attacks.

Indian Prime Minister Manmohan Singh and his Pakistani counterpart Yusuf Raza Gilani agreed on Thursday to fight terrorism jointly but Singh insisted Pakistan must punish those responsible for the Mumbai attacks if it wants formal talks.

Clinton, in an opinion piece published in the Times of India newspaper on Friday, wrote that both India and the United States had experienced searing terrorist attacks.

We both seek a more secure world for our citizens. We should intensify our defense and law enforcement cooperation to that end. And we should encourage Pakistan as that nation confronts the challenge of violent extremism, she wrote.

Singh said the agreement with Gilani had not diluted India's position that Pakistan must stop militant groups using its territory to carry out attacks on Indian soil as a precondition for resuming peace talks, known as the composite dialogue.

India paused the talks after the attack on Mumbai last November, in which 166 people were killed.

It only strengthens our stand that we wouldn't like Pakistan to wait for the resumption of the composite dialogue ... but take action against terrorist elements regardless of these processes that may lead to resumption, Singh told parliament on Friday.

ACTION CANNOT AWAIT

Singh was answering an opposition accusation that the agreement with Gilani was a reversal since it removed the link between the five-year peace talks and fighting terrorism.

Action on terrorism ... cannot await other developments, Singh said.

Since the attacks, Washington has sought to cool tensions between the nuclear-armed neighbors so it can keep Pakistan's army focused on fighting Taliban militants on its western border with Afghanistan, and not on its eastern frontier with India.

The two countries have fought three wars since independence from Britain in 1947, two of them over the disputed Himalayan region of Kashmir.

That enduring dispute spawned militant groups like Lashkar-e-Taiba (LeT), which India blames for the attack on Mumbai, and others backed by Pakistan's Inter-Services Intelligence spy arm as proxies against India.

Talat Masood, a former Pakistani army general based in Islamabad, said Pakistan would have to work hard to neutralize the influence of militant groups if it wanted better India ties.

There will be no genuine or real talks ... till such time that the Indians are satisfied ... that the perpetrators of the crime of Mumbai are brought to justice, Masood told Reuters.

India was infuriated in June when a Pakistani court freed LeT founder Hafiz Mohammad Saeed, wanted over the Mumbai attack along with 21 other Pakistanis named in Indian arrest warrants. Earlier this month, Pakistan appealed the court's decision.

(Additional reporting by Augustine Anthony in ISLAMABAD; Editing by Paul Tait)

Hillary Clinton Barack obama Terrorism Pakistan