Shares in embattled support services group Jarvis went into freefall yesterday after it announced it had asked for another £ 17 million of lending.

The company said it continued to have the support of its lenders after bankers agreed to loan it the extra cash.

Jarvis, which was once Britain's biggest construction and engineering firm, said it needed the money to meet greater than anticipated working capital requirements.

It described the latest funding as a vote of confidence in its future, although it still has to complete a balance sheet overhaul this summer.

But the City saw the announcement differently, with shares in the company falling by a third in early morning trading.

The statement came two months after the group's extension of banking facilities to March 2006 rescued it from the brink of collapse.

The company - valued at £24 million on the stock market - is still an estimated £280 million in debt and is looking at ways to reduce that figure.

A debt-for-equity swap - a move that dilutes the value of existing shareholdings - is a "likely" option, the company added.

Jarvis, which did not disclose the reasons behind its need for an extra £17 million of working capital, had said in December that it would not need extra financing.

Chief executive Alan Lovell said: "These agreements are positive steps which demonstrate the ongoing support of our lending group.

"We've got some working capital issues, the vast majority of which are purely timing."

The company also said it had modified the terms of existing finance facilities.

Shares in Jarvis closed last night down 3.25p to 13.75p.