Imperial Tobacco surprised investors today as the world's fourth largest cigarette maker launched a larger than expected rights issue to raise £4.9 billion.

The rights will be offered at a deep 43 per cent discount to last night's closing share price. Imps' shares fell almost 3 per cent in early deals.

The issue is fully underwritten and will help pay for last year's bumper acquisition of Altadis, the Spanish cigarette maker.

The deal is one of the largest in UK corporate history and comes as a growing list of British companies take the begging bowl to existing shareholders for much-needed cash.

Proceeds will help pay off some of the debt associated with the acquisition, which completed in January.

Adam Spielman, analyst at Citigroup, said the size of the discount should not matter to shareholders, but the amount raised should. "Many had been estimating a figure closer to £4 billion," he said.

Analysts at Credit Suisse said they had expected a discount of 35 per cent.

At the same time, the world's fourth largest tobacco group reported a 45 per cent slide in first half profits, down from £421 million to £233 million for the six months to the end of March as it faced up to difficulties integrating the acquisition.

The issue is fully underwritten by Morgan Stanley, Lehman Brothers, Citigroup and Hoare Govett.

Royal Bank of Scotland, the banking group, is asking investors for up to £12 billion, while HBOS, which owns Halifax, has launched a cash call for £4 billion.

Johnston Press, the regional newspaper group, last week said it would try to raise £212 million by offering new shares to existing owners.

Imperial, which makes Lambert & Butler and Gauloises brands, is offering one share for every existing share at £14.75 each.

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