London - British fund managers raised their exposure to cash to the highest level in at least two years in December as a flight to safety accelerated on disillusionment with the eurozone's ability to solve its debt crisis, a Reuters poll showed on Monday.A survey of 15 investment managers found average cash allocations in global balanced portfolios jumped more than 1 percentage point to 10.4% in December. Their holdings of stocks dropped by a similar margin to 48.9% from 50% a month earlier.While 2011 has seen an unprecedented succession of financial, economic and political shocks from the Arab Spring to the Japanese tsunami and the escalating eurozone debt crisis, many investors hold scant hope that 2012 will be much calmer."One would hope there would not be as many 'acts of God' in 2012, but the potential for market upsets and systemic crises remains high," said Chris Paine, associate director for asset allocation at Henderson Global Investors.Failure to resolve the eurozone crisis and ensure the single currency's survival in its current form remains high on the list of fund managers' concerns for the coming year.Financial markets were underwhelmed by an EU agreement on new budget rules this month to tackle the debt crisis.Investors are also concerned about slowing global growth and uncertainty about the prospects for key emerging markets such as China and India."Modest global growth profiles when compared with historical recoveries remain one of many concerns," said Paul Amer, investment manager at Insight Investment.However, while subdued economic growth and the eurozone debt crisis will weigh on stock markets, some investors favour stocks longer-term given low valuations and a pool of companies in a relatively strong financial position."Despite the more lacklustre prospects for economic growth next year, we are positive on the longer-term prospects for equities, reflecting low valuations and the relatively strong financial positions of many companies," said Alec Letchfield, chief investment officer, wealth at HSBC Asset Management."However, further volatility is likely and downside risks remain in the event of another escalation of the eurozone crisis."