Fidelity International's Trevor Greetham has warned the "fiscal masochism" of US and European policies is leading to a new risk of recession and stagflation.
F&C's Ted Scott said if UK equities dive a further 5% they will be worth stockpiling, despite the risk of a double-dip recession.
The FTSE 100 has entered bear market territory, having now fallen 20% from recent highs after the index lost as much as 5% in early trading on Tuesday.
Growth in the UK has deteriorated for the sixth consecutive month while the global recovery has peaked, according to the Organisation for Economic Co-operation and Development (OECD).
Bank of America's share price fell by 20% as US financials were routed in Monday trading over growth fears and S&P's downgrade of the US credit rating.
J.P. Morgan's Nick Gartside has warned France and the UK are in danger of joining the US in losing their prestigious AAA-credit ratings.
The FTSE 100 dipped below the 5,000 mark this morning after a short-lived rally at the start of trading.
The US was hit with a further blow today as Standard & Poor's warned the economy is unlikely to regain its AAA-credit rating anytime soon.
Heavy losses in the battered US markets have spread to the UK and sent the index of 100 leading shares down more than 3%.
Hedge funds saw the majority of their gains for this year wiped out on Friday, losing over 1% of their value in just 24 hours.