Growth in the US picked up slightly in the third quarter, helped by stronger consumer spending, although the recovery of the world's largest economy remains sluggish.

The data – the last snapshot of the country's economic health before voters elect a new Congress on Tuesday – showed that gross domestic product grew at an annualised rate of 2% between July and September. This was exactly in line with economists' forecasts and comes after 1.7% growth in the second quarter and 3.7% in the first.

Commenting on the figures, Barack Obama said the US must boost growth to heal the damage done by the most severe recession in decades. "As we continue to dig out from the worst recession in 80 years, our mission is to accelerate that recovery and encourage more rapid growth," the president said.

The data eased fears that the economy might be sliding into a double-dip recession, but did not alter market expectations that the Federal Reserve will resume its policy of pumping billions of dollars into the economy next week.

The dollar weakened against major currencies after the figures, hitting an 11-day low below $1.60 against the pound.

Peter Boockvar, equity strategist at Miller Tabak in New York, said: "Growth was ordinary in the third quarter after an ordinary growth rate of 1.7% in the second quarter and unfortunately is not expected to get much better in the fourth quarter. The economy is still growing but below its potential."

Consumer spending was slightly stronger than expected, rising by 2.6%, while business investment in equipment and software surged by 12% and government spending increased by 3.4%. There was a contribution from companies rebuilding their stock levels, but imports surged 17.4% and exports worsened.

James Knightley at ING in London said: "With concerns about the economic outlook persisting and inflation pressures fading further, this won't alter the outcome of the federal open market committee meeting on Wednesday. The Fed seems to be hinting at an incremental programme, perhaps lasting six months, but which could be extended depending on the newsflow. Consequently, while the market may be disappointed by a 'small' announced figure for QE, the actual end result could end up being far higher, perhaps even more than in the first round of QE."Stock markets have rallied in recent weeks in anticipation of further quantitative easing, dubbed "QE2", at the Fed's November meeting, although it is uncertain how much the Fed would pour into the economy.

It has already injected $1.7tn (£1tn) through asset purchases to revive the flagging recovery.

Lakshman Achuthan and Anirvan Banerji, of the Economic Cycle Research Institute, which forecasts business cycle turns, said: "The economy will avoid a double dip. But the bad news is that a revival in economic growth is not yet in sight. The slowing of economic growth that began in mid-2010 will continue through early 2011. Thus, private-sector job growth, which is already easing, will slow further, keeping the double-dip debate alive."

While the US economy has grown in each of the past four quarters, unemployment has remained high, with the jobless rate stuck for the past two months at 9.6%. Even so, consumer spending, which accounts for 70% of US GDP, has remained surprisingly resilient.

The US economist Nouriel Roubini warned that Obama was heading for a "fiscal train wreck". In an article on Friday, he said: "Mr Obama may take some comfort from the fact that the worst of the coming fiscal train wreck will be prevented by the Fed's easing. But the risk is he will then preside not over a bout of inflation but a Japanese-style stagnation, where growth is barely positive, and deflationary pressures and high unemployment linger."

The Bank of Japan has brought forward its meeting by a week to Thursday and Friday, triggering speculation that Japan's central bank intends to respond to any stimulus measures from the Fed with further QE of its own.

The Bank of England meets on Wednesday and Thursday, but is not expected to introduce further economic stimulus until next year, if at all, after surprisingly strong growth figures this week. The European Central Bank is also likely to sit on its hands at its meeting on Thursday.