Sir Richard Branson’s Virgin Group will collect a super-bonus if it meets certain performance targets as part of its proposed acquisition of Northern Rock, The Times has learnt.

The windfall for the mobile phones and airlines giant will come in the form of a “performance warrant” to be paid only when strict return targets have been met for all shareholders.

Details of the super-bonus have been kept under wraps but it is believed that more information will become available when Sir Richard’s consortium publishes the prospectus for its planned share issue. A Virgin spokesman said: “It is under consideration now. Everything will be made public before any decisions are made.”

The super-bonus is one way that Virgin hopes to extract longer-term value from its £200 million upfront investment in Northern Rock. In addition, the billionaire Virgin boss will receive fees from the beleaguered bank for the use of the Virgin brand name. Sir Richard and his partners also plan to cross-sell Virgin Money products, such as a new mortgage range, to Rock customers as another way of driving fresh revenue.

The consortium, which includes Wilbur Ross, the US billionaire who specialises in restructuring troubled companies, is also counting on a pickup in the Rock’s share price once things have settled down and the bank is able to grow its deposit base by leveraging the Virgin brand.

News of the sweetener comes as sources said yesterday that Virgin was pressing full-speed ahead with its proposed takeover after being named preferred bidder this week by the Rock and the Tripartite Authorities of the Bank of England, the Treasury and the Financial Services Authority.

Citigroup, Royal Bank of Scotland and Deutsche Bank, which have agreed to provide £15 billion of liquidity for Virgin’s bid, will spend the next two weeks completing their due diligence and obtaining clearance from their credit committees to sign off formally on the deal. Although it is possible for the banks to pull the plug, one source said that Sir Win Bischoff, Sir Fred Goodwin and Josef Ackermann, the chief executives of the three lending banks, had already “emotionally signed off on the deal”.

It is understood that Philip Richards, the chief executive of RAB Capital, the 6.7 per cent Northern Rock investor that has been most vocal about shareholder rights, spoke to Sir Richard on Monday night by telephone. Sources said that RAB was not against Virgin’s bid but thought it too dilutive to shareholders. Mr Richards is also unconvinced about the management pedigree of Jayne-Anne Gadhia, the Virgin Money chief executive, who would take over as chief executive of the enlarged group.

Under Virgin’s plan, shareholders could end up owning 45 per cent of the new group if they subscribed to a 25p-a-share rights issue. Equally, however, if they do not stump up the cash, they will be diluted to a 6 per cent holding. The Virgin consortium will own the remaining 55 per cent, with Virgin itself believed to get slightly less than 30 per cent of the holding.

Meanwhile, SRM Global Master Fund, another key Rock shareholder, lifted its stake in the mortgage lender to 8.5 per cent from 6.8 per cent by buying 6.9 million shares at £1.09 an issue.

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