Britain’s top share markets fell on Friday, as worry over the United States’s looming fiscal cliff overshadowed robust U.S. consumer sentiment data.

The FTSE 100 closed down 6.37 points, or 0.1 percent at 5,769.68, after a choppy session in which it sunk to a two-month low at 5,715.23.

Traders cited concern about the U.S. fiscal cliff – of about $600 billion in spending cuts and tax hikes set to begin at the start of 2013 – as a major factor behind the index’s weakness.

The fiscal cliff, which may jeopardise growth, has long been a known issue, but has been making the headlines in recent days due to focus on the post-election political landscape.

The gloom lifted in the afternoon on the release of data indicating Americans were more upbeat about the outlook for their economy. U.S. consumer sentiment hit its highest level in more than five years in November, according to the Thomson Reuters/University of Michigan preliminary index of sentiment.

Trade was thin during the session, making the index’s moves both ways more pronounced. Volumes picked up to 100 percent of its 90-day daily average by the close – though that 90-day average is itself weak.

There’s very little volume, very little interest. Just a little bit of a strike on some better U.S. numbers and a few people closing down their shorts ahead of the weekend, Andy Ash, head of sales at Monument Securities, said.

The FTSE’s failure to stay below the important 200-day moving average, at 5,728, was also behind the short-covering going into the close, traders said.