LONDON A lukewarm recovery from recession and falling inflation will spur the Bank of England to top up its asset-buying programme with another 50 billion pounds next month, a Reuters poll showed on Thursday.
The economy, meanwhile, probably bounced back to growth of 0.6 percent last quarter, supported by better weather, extra working days and the London Olympic Games, the poll of more than 70 economists taken in the past week predicted.
But it will only expand between 0.2 and 0.4 percent in the following four quarters, according to forecasts unchanged from a poll taken last month.
"Indicators suggest the economy is barely achieving some growth, which means the BoE will probably have to downgrade its growth forecast again - and continue to add to stimulus with more QE in November," said Azad Zangana at Schroders.
Britain fell back into its second recession in four years at the turn of the year as tough government austerity measures and the euro zone debt crisis stifled the economy.
Gross domestic product contracted for a third quarter between April and June, by 0.4 percent, depressed by one-off factors including unusually wet weather and an extra public holiday to mark Queen Elizabeth's 60 years on the throne.
The International Monetary Fund cut its economic forecasts for Britain on Monday and said more BoE stimulus - and possibly higher public spending or tax cuts - may be needed if the outlook darkens.
The IMF forecast Britain's economy would shrink 0.4 percent this year, before growing by a 1.1 percent in 2013, down sharply from its July forecasts of 0.2 percent growth in 2012 and 1.4 percent growth the year after.
Britain's GDP will end the current year 0.3 percent smaller than how it started, the Reuters poll said, knocked by a downturn in the euro zone - its biggest export market - but agreed with the IMF's 2013 prediction.
The poll's 2013 forecast slipped for a fourth month and the IMF said a mix of government austerity, the crisis in parts of the euro zone and an overhang of indebtedness from before the global financial crisis are weighing on Britain's prospects.
The jobs market does not look quite as bad as previously feared, with unemployment averaging 8.1 percent this year and 8.3 percent next, revised down sharply from a July poll.
The number of Britons on unemployment benefits dropped in August by the largest amount in two years, raising hopes that improved prospects will allow consumers to spend more and get the recovery going.
The poll found there was a 70 percent chance the Bank will add to the 375 billion pounds it has already spent through its quantitative easing asset-purchase programme, up from 60 percent in a September 27 poll.
The majority of respondents who answered said Monetary Policy Committee Members will announce the move next month.
"It's not definite because they all sound like they don't want to do it but they probably will. If they don't do it then they will do it soon after - there is weakness in the economy," said Michael Saunders at Citi.
Minutes from the October MPC meeting are due next week. Governor Mervyn King said on Tuesday monetary policy cannot prop up Britain's economy forever, but added there was no immediate barrier to stop it buying more bonds.
Paul Tucker, deputy governor and favourite to replace King when he retires next June, said late last month quantitative easing had lost some of its bite, but was still effective.
His colleague, Martin Weale, said on Thursday another round may not be "compatible" with the Bank's inflation target.
The Bank cut its main interest rate to a record low of 0.5 percent over three years ago. Median forecasts from the poll do not see any movement until April 2014 at the earliest, unchanged from recent polls.
(Polling by Snehasish Das and Somya Gupta. Editing by Jeremy Gaunt.)