UPDATE 1-UK Stocks-Factors to watch on March 21
(Adds futures, company news)
LONDON, March 21 (Reuters) - Britain's FTSE 100 index is set for a slightly lower open on Friday, with futures down 0.1 percent by 0730 GMT ahead of the cash market open. For more on the factors affecting European stocks, please click on
* The UK benchmark closed down 30.69 points, or 0.5 percent, at 6,542.44 points on Thursday. The index's decline leaves it just 2 percent above an early February low, and down 3.1 percent this year.
* Shares of companies with a big exposure to Russia could come under further pressure after Washington extended sanctions and Fitch revised the country's outlook to 'negative'.
Drinks cans maker Rexam, cigarette maker British American Tobacco, and catering firm Compass Group are among UK blue-chips with the biggest exposure to Russia, according to data from index provider MSCI.
For a list of European blue-chips with the biggest exposure to Russia: