European stock markets fell for the fourth straight day Friday, undermined by another downward revision to first quarter US growth figures. Asian markets earlier in the day also extended losses on renewed nervousness for global recovery prospects. Wall Street opened in positive territory but momentum quickly turned negative. As leaders of the Group of 20 developed and developing countries were gathering for a summit in Toronto, where differences in US and European economic strategies were threatening to emerge, the United States again issued a downward correction to its growth figures. The Commerce Department said the economy grew at a weaker-than-expected 2.7 percent rate in the first quarter, a third and final revision. The estimate was the second downward revision of gross domestic product growth for the January-March period, which was initially calculated at 3.2 percent before being adjusted down to 3.0 percent in late May. Analysts at Briefing.com said the final figure was 'disappointing,' adding that 'the negative revision was unexpected.' But they said that 'the fact that GDP remained near its potential 2.8 percent long-term growth rate will not alter our view about the stability of the economic recovery.' The news nonetheless dampened sentiment in Europe, where investors and analysts were awaiting the outcome of the G20 meeting this weekend. The United States ahead of the summit has voiced fears that too hasty a withdrawal of stimulus spending in Europe, in order to reduce deficits, could derail a global recovery. In Paris, a stock market trader said: 'The downward revision for the second time in first quarter US growth combined with first disappointing financial results statements from US companies weighed on the Paris market.' The London FTSE 100 index lost 1.05 percent to close at 5,046.47 points while in Paris the CAC 40 gave up 1.00 percent to finish at 3,519.73. The Frankfurt the DAX lost 0.73 percent and closed at 6,070.60 points. Elsewhere there were losses of 0.72 percent on the Swiss Market Index, 0.58 percent in Brussels and 0.54 percent in Madrid. The Milan exchange managed a 0.10 percent gain. In London BP was among the day's big losers, plunging at one point to a 14-year low after the group ramped up the costs so far of its oil spill crisis in the Gulf of Mexico to 2.35 billion dollars (1.9 billion euros). The company's stock collapsed by almost nine percent in mid-morning trading to plumb a low of 296 pence on the London Stock Exchange, hitting a level last seen in August 1996, as investors showed alarm over spiralling costs. Shares later pulled back slightly to end at 304.6 pence, down 6.35 percent. In Paris cyclical stocks, dependent on robust growth momentum, lost ground. Auto maker Renault shed 2.94 percent, chemical group Rhodia fell 3.49 percent and steel giant ArcelorMittal shed 3.02 percent. In Frankfurt the auto sector was under particular pressure. Daimler lost 3.25 percent, Volkswagen 2.80 percent and BMW 2.42 percent. US stocks rose slightly at the open as investors digested a sweeping financial reform bill. But the Dow Jones Industrial Average by mid-day was down 0.44 percent at 10,107.91 while the tech-rich Nasdaq had lose 0.17 percent to reach 2,213.59. The financial reform bill needs approval by both chambers in the Democratic- controlled Congress before it heads to President Barack Obama's desk for signing. 