City bonuses are predicted to shrink by nearly 60% this year - but a few finance executives can still expect to pocket big payouts, an economic consultancy said.

The Centre for Economics and Business Research (Cebr) said City workers would receive bonuses worth more than £3.5bn this year and more than £2.7bn in 2009 - a sharp drop compared with the £8.5bn paid out in 2007.

Cebr said that the global credit crunch had ushered in "a new culture of bonuses", with payments in excess of £1m likely to be "few and far between", though some hedge funds that have profited from the financial turmoil could be in a position to pay out "megabucks".

Prime Minister Gordon Brown yesterday declared the era of massive bonuses for City executives over and pledged to rein in "irresponsible" bankers.

Mr Brown said: "Our economy is built around people who work hard, who show effort, who take responsible decisions, and where there is excessive and irresponsible risk-taking, that has got to be punished."

Richard Snook, Cebr chief economist, said: "This is not the end of the bonus system. But there is a new culture of bonuses around. The million-pound-plus bonuses are going to be few and far between."

Tory leader David Cameron said no directors of banks taking advantage of the bailout package should get a bonus this year.