Wall Street's Lehman Brothers, one of the City's most influential investment banks, is set to reveal losses topping $2 billion (£1.01 billion) for the second quarter.

The loss, flagged by the Wall Street Journal, is far more than the $300 million predicted by analysts, and comes after a week of speculation about the scale of the problems at the bank.

Lehman is said to be close to raising some $5 billion in fresh capital from various investors, in hopes of putting an end to rumours of a liquidity crisis.

Investors in the fundraising include the New Jersey Division of Investment, which manages the state's $80 billion of pension funds, and possibly CV Starr, the investment vehicle of former American International Group chief executive Maurice Greenberg, the Journal reported.

There is also talk of a foreign investor, possibly from the Middle East.

The capital-raising would come primarily through common shares, the first such issue since Lehman went public in 1994.

Lehman shares have lost about 50% of their value this year as investors have become alarmed at its exposure to the mortgage market.

The bank had been due to report quarterly results next week, but is now expected to release them early in a bid to put an end to rumours.