Chief executive Brian Staples will step down at the end of next month, Amey said in a statement.

Mr Staples had come under pressure to resign following a grim year for the company.

On Monday, Amey issued its second profit warning in six weeks.

The firm blamed problems in selling its stake in government contracts to build or maintain public service facilities.

Moving on

Amey said Mr Staples' departure had been agreed with the board.

"It's consistent with what we have said in the past, that (Mr Staples) had certain projects he wanted to finish and at that point would then move on," an Amey spokesman said.

Amey's share price fell by 93% during 2002.

The company was heavily involved in the government's private finance initiative (PFI), a scheme which sought to get private companies to fund public service facilities in return for a guaranteed revenue stream from the government.

But in March last year the firm stunned investors when it unveiled an unexpected loss after it changed its accounting procedures for PFI projects.

Worries over the firm's position increased in October when its finance chief Michael Kayser quit the post only five weeks into the job.

Amey's PFI contracts are now up for sale. But Monday's profit warning came after the firm said the sale of the contracts would be delayed and for a lower price than originally expected.

Tube progress

Amey's financial problems delayed the completion of a contract to help run the London Underground's Piccadilly, Northern and Jubilee lines.

But on Tuesday, the deal was finally signed by the Tube Lines consortium - which includes Amey along with engineering firms Jarvis and Bechtel.

The consortium will spend about £16bn upgrading the Underground network over the next 15 years.