A series of Reuters polls showed British, continental European and Japanese fund managers increased their holdings of US equities, while US managers held steady.

At the same time, the polls of 47 investment managers and strategists showed non-US investors were cutting back on holdings of Euro zone equities, even after the European Central Bank and its Group of Seven counterparts intervened to support the slumping euro.

Strategists said the recent rise in oil prices was likely to fuel financial markets volatility in the months ahead, an environment in which US stocks were likely to outperform other major markets.

"We stick to our scenario that we're going to see a more or less soft landing in the US, but we consider also the threat arising from the persistently high oil price as well as further rate hikes which might undercut euro zone growth," said Martin von Hagen, a portfolio manager with Commerzbank International Capital Management in Frankfurt.

"To cope with this risk scenario we have adjusted our positions a little bit in favour of the US."

British and euro zone investors were among the keenest buyers of US stocks. European managers increased their average allocation to US equities to 52.3 per cent in September from 49 per cent in August, while trimming exposure to euro zone equities to 20.3 per cent from 20.4 per cent.

British managers boosted allocations to US equities for the sixth straight month pushing weightings up to an average of 41.2 per cent of equity portfolios, from 39 per cent last month, while cutting euro zone equities.

Japanese investors also bought more US and Canadian stocks, increasing allocations to 41.01 per cent from 40.20 per cent, while cutting back on euro zone stocks and bonds.

US fund managers were the only ones polled who turned more optimistic on European equities, increasing allocations to stocks in the 11-nation euro zone to 20 percent from 18 percent in August's survey.

"I imagine some people are trying to call the bottom," said Tom Van Leuvan, global equity market strategist at JP Morgan.