Copper slipped from a four-month high on Friday, but prices were on track for their third straight week of gains, with the prospect of additional U.S. stimulus moves supporting sentiment.

Three-month copper on the London Metal Exchange lost 0.52 percent to $8,545 a tonne by 0719 GMT, reversing some of the previous session's gain of 2.5 percent. The metal is headed for a 4 percent increase this week and a 12 percent jump this year, following a 21 percent drop in 2011.

Federal Reserve Chairman Ben Bernanke said this week the U.S. central bank was ready to offer the economy additional stimulus after it announced it was likely to keep interest rates near zero until at least late 2014.

The Fed was more dovish than expected, and that was positive for markets, said Ong Yiling, a commodities analyst at Phillip Futures in Singapore.

But beyond the Fed, investors want to lock in profits after a recent run-up, while there's also caution before the resolution to the Greek debt talks and the first reading of U.S. fourth-quarter GDP.

The United States, the world's largest economy, will release its economic growth figures for the three months ended December at 1330 GMT.

The Shanghai Futures Exchange is closed this week for the Lunar New Year holiday.

Japanese copper smelters are talking with miners in Canada and elsewhere over copper term processing fees for 2012, aiming to clinch fees of more than $63.5 a tonne and 6.35 cent a pound after breaking up talks with global miner BHP .

Freeport-McMoRan Copper & Gold was loading two ships at its Indonesian port, sources said on Thursday, in a fresh sign that work at the world's second-largest copper mine is returning to normal after a three-month strike.

Anglo American posted a rise in quarterly output for its key commodities, with iron ore up and copper boosted by a ramped-up Los Bronces mine in Chile.

Two of the world's biggest iron ore carriers are due to arrive in the Philippines for the first time next month, shipping data showed, as Brazilian mining giant Vale looks to use the country as an alternative base to reach Chinese ports.

The euro held on to recent hefty gains against the dollar on Friday, after hitting a five-week high, as the Fed's pledge to keep rates near zero for the next three years encouraged carry trades funded in dollars.

Greece and its private creditors will continue talks on debt restructuring on Friday with the aim of sealing an agreement within a few days after making progress on Thursday.