TOKYO, Oct 9 (Reuters) - Japanese stocks were on course for their biggest weekly gain in two months on Friday, on hopes of more stimulus in the United States, even though some investors doubted the chances of a deal in the run up to the U.S. presidential election.

The Nikkei 225 Index slipped 0.07% to 23,629.73 by 0158 GMT on Friday. For the week, however, the Nikkei added 2.6%, marking its largest gain since the week ended Aug. 14.

The broader TOPIX fell 0.43% to 1,648.30. For the week, the TOPIX was up 2.4%.

U.S. President Donald Trump said talks with Congress had restarted on targeted fiscal relief, after abruptly calling off negotiations earlier this week.

However, Democrat House Speaker Nancy Pelosi downplayed the likelihood of stand-alone bills, and relations between the two political parties are likely to become more strained as a hotly-contested presidential election on Nov. 3 draws near.

The U.S. economy, struggling with a rise in cases of the novel coronavirus, is certain to lose momentum without a new stimulus, and this is a risk for Japan's export sector.

The largest percentage gainers on the Nikkei index were convenience store operator Seven & i Holdings Co Ltd, up 5.43%, followed by car battery-maker GS Yuasa Corp, gaining 3.03%, and clothing retailer Fast Retailing Co Ltd , up by 2.81%.

The largest percentage losses on the index were drugs-maker Daiichi Sankyo Co Ltd, down 3.95%, followed by engineering conglomerate JGC Holdings Corp, losing 2.99%, and Mitsubishi Motors Corp, down 2.97%.

There were 47 advancers on the Nikkei index against 174 decliners.

The volume of shares traded on the Tokyo Stock Exchange's main board was 0.46 billion, compared with the average of 1.15 billion in the past 30 days. (Reporting by Stanley White; editing by Uttaresh.V)