* Dollar lifted by Fed official's comments on QE
* Gold prices set to end the week down nearly 5 pct
* Palladium, platinum outperform after Platinum Week (Updates prices)
By Jan Harvey
LONDON, May 17 (Reuters) - Gold fell for a seventh straight session on Friday, its longest losing streak in four years, after comments from a Federal Reserve official that the bank may soon rein in monetary easing lifted the dollar.
The U.S. unit approached a 10-month high against a basket of currencies after San Francisco Fed chief John Williams said the U.S. central bank could begin easing up on stimulus this summer.
While Williams is not a voter this year at the Federal Open Market Committee, his views carry weight as he is considered close to top Fed officials.
That stunted a brief rally seen in gold prices late on Thursday after a batch of soft U.S. data, putting it on track to fall 5 percent this week, its biggest weekly drop in four.
Spot gold was down 0.6 percent at $1,376.85 an ounce at 1155 GMT, while U.S. gold futures for June delivery were down $11.30 an ounce at $1,375.60.
"In the main, the current price weakness is to be attributed to strength in the dollar and massive selling in exchange-traded funds," Sharps Pixley chief executive Ross Norman said.
"We've had some poor data out of the United States, yet the dollar still continues to rise. Clearly a correction in the U.S. dollar would be massively supportive for gold."
ETFs - popular investment vehicles that give investors exposure to the gold price through issuing securities backed by physical metal - have seen massive outflows this year.
The largest, New York's SPDR Gold Trust, reported an outflow of another 5.7 tonnes on Thursday, bringing the drop in its holdings this week to more than 10 tonnes.
Physical demand for the metal, which spiked after prices posted their biggest two-day drop in 30 years in April, showed signs of softening.
Buying in India, the main consumer of the precious metal, had fallen significantly from Monday, which saw the celebration of Akshaya Tritiya, considered an auspicious day to buy gold, one gold trader in Singapore said.
Platinum group metals were the best performers this week, with palladium up 4 percent as refiners, recyclers, consumers and traders attended Platinum Week in London.
"The outperformance of PGMs, and particularly palladium, is consistent with overall positive views expressed by majority of industry participants with whom we've spoken," UBS said in a note. "Preference for palladium is more evident than ever."
"Investors appear to be banking on the strong fundamental story and the implications this has on the medium and long term, perhaps choosing to position themselves sooner rather than later," it added. "We expect dips to be bought and for PGMs to stay supported overall."
Spot platinum was down 0.5 percent at $1,469.74 an ounce, while spot palladium was down 0.7 percent at $730.97 an ounce.
Platinum has benefited from concerns over industrial unrest in major producer South Africa. Miners at South Africa's Anglo American Platinum reported for work on Friday, a company spokeswoman said, despite earlier calls for a strike by some union leaders.
Platinum extended its premium over gold to a 2-1/2 year high at $94 an ounce, having maintained a historically unusual discount to the yellow metal for much of the previous two years.
Silver tracked gold lower, falling 5.8 percent on the week to $22.44 an ounce. It was down 1 percent on the day. (Reporting by Jan Harvey, editing by William Hardy)