European stock markets are expected to open lower on what looks set to be another volatile trading day.
The expiration of futures contracts and weakening confidence should also push the market down.
Financial bookmakers said the FTSE 100 share index would open 40-50 points lower after it closed at 3,813 yesterday.
"The penny has finally dropped. For the last few weeks people have used war and September 11 as a reason why the economy's struggling but now war seems inevitable, we've got past that date, and the outlook for the economy is still dire," said Mr Freddie Tulloch of Financial Spreads.
Traders said firms such as British Airways, music publisher EMI and electricity generator International Power will get extra attention as fund managers reshuffle their portfolios on the last day of FTSE 100 trading for all three companies.
The expiry of FTSE 100 stock index futures and options at 10.30 a.m. is expected to add to stock market volatility. In the United States investors have "triple-witching" - or the simultaneous expiry of stock index futures, options and individual stock index options - to contend with.
Among smaller-cap standouts, shares in Bloomsbury Publishing, the publisher of the Harry Potterbooks, will be in focus after author J.K. Rowling, the creator of the tales, won a plagiarism case.