U.S. stock index futures pointed to a higher open on Friday as investors awaited key monthly data on the labor market.

U.S. May non-farm payrolls were forecast to fall by 520,000, a slowing from the loss of 539,000 jobs in April, although the previous month's number could be revised. The U.S. unemployment rate is seen rising to 9.2 percent in May from 8.9 percent in April, according to Reuters poll.

This morning's jobs number is going to be critical in terms of giving us a picture of what's going on, said Paul Mendelsohn, chief investment strategist at Windham Financial Services in Charlotte, Vermont.

Today's number is either going to confirm that the numbers are improving, or at least not getting any worse. But if that number comes in worse than expected, and if on top of that you've got a worse-than-expected revision to the previous month's number, then the market is not going to look at that favorably.

Global miner Rio Tinto rejected $19.5 billion in funding from China's Chinalco on Friday in favor of a cost-saving iron ore joint venture with rival BHP Billiton and a share sale to cut debt. Aluminum producer Alcoa Inc rose 2.9 percent to $11 in premarket trade.

S&P 500 futures rose 5 points and were above fair value, a formula that evaluates pricing by taking into account interest rates, dividends and time to expiration on the contract. Dow Jones Industrial Average futures added 54 points, while Nasdaq 100 futures gained 5.75 points.

Apple Inc shares rose 1.9 percent to $146.49 in premarket trade after the Wall Street Journal reported that Chief Executive Steve Jobs is on track to return to the company from a medical leave after being treated for a rare type of pancreatic cancer.

The Journal also reported the Federal Deposit Insurance Corp is aiming to shake up Citigroup Inc's top management, including replacing CEO Vikram Pandit, citing people familiar with the matter. Citigroup shares added 0.8 percent to $3.60 in premarket trade.

A U.S. federal appeals court will hear arguments on Friday to block the sale of Chrysler LLC to a group including Italian carmaker Fiat SpA and the U.S. government, arguing it violates longstanding bankruptcy law. The ruling will have implications for General Motors Corp , which filed for bankruptcy on June 1.

European shares traded higher by midday, led by Rio Tinto, after the mining group backed out of a planned tie-up with Chianlco and announced a rights issue while planning a joint venture with BHP Billiton .

Asian shares, oil and higher-yielding currencies rose as positive signals from the latest U.S. weekly job data sparked tentative optimism ahead of the Friday employment report.

U.S. shares climbed Thursday as a brokerage's upbeat view on U.S. banks sparked a run-up in financials, while surging prices in oil and other commodities boosted natural resource companies on hopes the economic slump was waning.

The Dow Jones industrial average <.DJI> gained 74.96 points, or 0.86 percent, to 8,750.24. The Standard & Poor's 500 Index <.SPX> climbed 10.70 points, or 1.15 percent, to 942.46. The Nasdaq Composite Index <.IXIC> rose 24.10 points, or 1.32 percent, to 1,850.02.

(Reporting by Chuck Mikolajczak; editing by Jeffrey Benkoe)

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