The Börse surprised the market by publishing its offer document, setting out concessions and commitments designed to appeal to LSE customers and its own shareholders.

The “pre-conditional offer” was pitched at “not less than” 530p an LSE share, valuing the Exchange at £1.3 billion, the same level as an earlier approach made before Christmas, although there is no guarantee that any offer will be made.

It was immediately rejected by the London exchange as not recognising the “inherent value” of the LSE. But London left the door open for a higher offer by expressing its willingness to continue talks with both bidders.

The publication of the document does allow the Börse to start talks with its investors, a number of whom have expressed disquiet over an LSE bid. A roadshow starts in Frankfurt today and arrives in London on Monday.

Euronext played down the significance of the Börse’s move. “I don’t think an awful lot has changed,” a source close to the company said. But in a formal statement, Euronext, which operates four continental exchanges, said that it would make a submission to the Office of Fair Trading about its own possible offer “imminently”.

This is seen as a necessary precursor to a formal approach to the LSE, and the company is believed to have raised a £1.4 billion war chest on the capital markets to fund a bid. But no offer is expected immediately.

The Börse made its own OFT filing yesterday. Werner Seifert, its chief executive, has made it clear that he wants an agreed deal with the LSE, although his offer says that the Börse reserves the right to waive this and go hostile.

Among his proposals to benefit customers in London, should a merger go through, are to provide a clearing service offering prices 50 per cent below those currently charged by LCH.Clearnet, although this might not be necessary if the latter makes “material” price cuts.

Mr Seifert, speaking to The Times, refused to discuss the possibility of a higher offer. “We consider 530p a good price,” he said. “There’s no other price on the table.” He also refused to contemplate a shareholder vote on an LSE purchase, for which a number of investors have called.

LSE shares ended 4½p higher at 579p, indicating a market expectation of offers rising.

Analysts welcomed the Börse’s decision to bring its intentions into the open. Johannes Thormann at the German bank WestLB, said: “Börse has put its cards on the table and put the ball in the court of LSE management and Euronext.”

THE DEUTSCHE BÖRSE OFFER IN FULL

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