* FTSE 100 falls 0.6 percent
* Banks slip, pressured by UBS results
* Miners, insurers fall but Reckitt Benckiser gains on SSL
By Simon Falush
LONDON, Oct 26 (Reuters) - Weaker financial and commodity stocks dragged Britain's top share index lower early on Tuesday, while Cairn Energy slid after negative drilling developments in Greenland.
By 0806 GMT, the FTSE 100 was 37.08 points, or -0.6 percent, lower at 5,714.90 after it added 0.2 percent on Monday.
Banks were mostly weaker, pressured as uncertainty on the global economic outlook kept optimism on more cyclical equities in check, while a loss at UBS's investment bank also weighed on the sector.
Standard Chartered fell 1.3 percent while Barclays lost 2 percent.
Optimism that the global economy is recovering soundly, supported in part by the prospect of the U.S. Federal Reserve printing more money has helped push the UK's blue-chip index up over 9 percent since the start of September.
However Fed officials have not been uniform in their comments about another round of quantitative easing, leading to some doubts in markets about how big such a programme will be. Kansas City Fed President Thomas Hoenig even called more asset buys by the central bank a "very dangerous gamble".
"There's an expectation that there will be additional quantitative easing and there's scope for disappointment if it doesn't come," said Philip Poole, global head of macro investment strategy at HSBC Global Asset Management.
Investors will watch UK growth data at 0830 GMT for more clues on the outlook for the domestic economy as the government prepares to enact harsh austerity measures to cut the deficit.
Economists polled by Reuters were unanimous that Britain's quarterly rate of gross domestic product (GDP) growth would slow sharply from the second quarter's nine-year high of 1.2 percent.
The median forecast for a fall in third-quarter GDP growth to 0.4 percent would take it below its trend rate of around 0.6 percent.
Insurers were weaker, pressured by a note from BofA Merrill Lynch which downgraded the sector on valuation grounds after a strong run over the past few months. Standard Life fell 1.5 percent and Prudential lost 1.6 percent.
Cairn Energy shed 4.7 percent after the oil explorer said one of its wells in Greenland did not result in a commercial discovery and another failed to reach target depth before the end of the Arctic drilling season.
Miners were also under pressure after ArcelorMittal forecast a far weaker fourth quarter than expected due to muted demand, lower prices and higher raw material costs. Rio Tinto and Anglo American both fell around 0.8 percent.
ARM Holdings was among the top fallers, down 5 percent as investors failed to react positively to solid third-quarter results from the chipmaker, with negative sentiment hitting the technology sector after Texas Instruments, which uses ARM designed chips, warned on its fourth-quarter revenue.
Reckitt Benckiser, by contrast, was a strong performer, up 1 percent after the British consumer goods firm won conditional EU regulatory approval late on Monday to purchase Durex condom and Scholl sandals maker SSL, boosting its presence in health and personal care.
The highlight of a batch of U.S. economic data due on Tuesday will be October's consumer confidence index, with an expected reading of 49.2, up from 48.5 in September.
The flow of U.S. third-quarter earnings will continue on Tuesday, with figures from Ford likely to be the main feature ahead of the New York open. (Editing by Karen Foster)