Top Blair aide to quit No 10 for City bank

One of Tony Blair's most trusted Downing Street aides has decided to quit Whitehall to take up a City job worth more than £300,000 a year.

Jeremy Heywood, the Prime Minister's principal private secretary and a man repeatedly described by Mr Blair as "indispensable", will join Morgan Stanley investment bank in the new year. His earnings at the US-owned bank, boosted by an annual bonus, will dwarf even that of Anji Hunter, Mr Blair's former Number 10 gatekeeper who joined BP for £200,000.

Even before Labour came to power in 1997, Mr Heywood's intellect had impressed his political masters. Norman Lamont, the former Chancellor, said that he was one of the most intelligent men he had met.

Having made a similar impression upon Gordon Brown, he was moved from the Treasury to Number 10 to advise Mr Blair on economics and domestic policy. He became a link man between Mr Blair and Mr Brown and has proved invaluable during various disputes between the two men in recent years.

He is understood to have decided to quit while on paternity leave this year.