NEW YORK (MarketWatch) -- Gold futures fell Monday for a third straight session to end near $870 an ounce, wiping out their yearly gains as traders shaved positions on worries that the 403 tons of gold sales by the International Monetary Fund will increase supply and depress gold prices.

Meanwhile, a stronger U.S. dollar also added downward pressures on gold prices.

"There is still this fear of a lot of selling coming from different central banks and the IMF," said George Gero, a precious metals trader for RBC Capital Markets. "The perception is that 'I am getting out of the way until all the sales are completed and let's see how it's absorbed.'"

Gold for April delivery fell $24.10, or 2.7%, to end at $871.50 an ounce in North American electronic trading. It dropped to as low as $865.10 earlier. The more active June contract also fell Monday, down 3.2% at $868.50.

Gold has lost nearly 6% since April 1 and is now down 1.4% for the year, partly out of optimism that collective actions by leaders of the world's major nations may stem the global economic crisis.

In spot trading, the benchmark London afternoon gold-fixing price stood at $870.25 an ounce Monday, down $34.75, or 3.8%, from the previous day.

In other metals futures, silver for May delivery fell 4.9% to $12.11 an ounce. June palladium was up 0.4% at $225.75 an ounce, while April platinum fell 1.2% to $1,145.70 an ounce.

May copper dropped 2.1% to $1.959 a pound.

IMF gold sales

Leaders from the Group of 20 nations said last Thursday they endorse 403 tons of gold sales by the IMF. The proceeds will be used to provide finance for the poorest countries over the next two to three years.

The announcement came one day after the European Central Bank said it had completed the sale of 35.5 tons of gold.

The IMF's plan to sell the gold still needs to be approved by an 85% majority vote from its 185 members. The U.S., which has 17% voting power in the fund, essentially holds veto power. See full story on IMF gold sales.

If the plan is approved, the gold selling will be implemented in coordination with major central banks to minimize the impact on the market, the IMF said.

The possible IMF gold sales helped gold prices move lower in the short turn, said Hussein Allidina, an analyst at Morgan Stanley. But he added he sees "any weakness in price as a buying opportunity as the sale would occur over years and be under the CBGA limit."

The second Central Banks Gold Agreement, or CBGA, caps total gold sales of the signatories at 500 tons a year and expires in September. A third CBGA is expected to be signed before September. See related story about central bank gold selling.

Also helping gold move lower Monday, the U.S. dollar rose against most of its major rivals Monday, with the dollar index DXY, +0.23% up nearly 1% at 84.767. See Currencies.

A stronger greenback tends to push down dollar-denominated prices of commodities such as gold and crude. Crude futures fell nearly 4% Monday.

Falling ETF investment

Investment in gold exchange-traded funds also stalled recently. Holdings in SPDR Gold Shares GLD, -0.54% , the biggest gold exchange-traded fund, stood at 1,127.37 tons Friday, down slightly from a day ago, according to latest data from the fund.

It's the first drop in SPDR holdings in one month. The SPDR lost 2.2% to $85.68 on Monday.

Investors seeking investment safe haven had been buying gold earlier this year as deepening troubles in the economy pushed stocks to their lowest level in decades. But actions from the world's major nations has boosted investment sentiment and reduced gold's safe-haven appeal.

The U.S. government and the Federal Reserve have spent, lent or committed more than $10 trillion to stem the economic downturn since the financial crisis began. Fed Chairman Ben Bernanke said in a speech Friday that he expects the gradual resumption of sustainable economic growth is coming.

The recent weakness in gold prices is "a sure sign risk appetite has increased further following the actions of various governments and central banks as well as the combined efforts of the G20 nations last week," said James Moore, a precious metals analyst at TheBullionDesk.com