Speculation that the New York Stock Exchange could launch a bid for its London counterpart is growing.
John Thain, the NYSE chief executive, was the subject of weekend speculation that he was consulting advisers about whether to table a rival offer.
But the group is understood to be at least six weeks away from acting, having just floated on its own market.
The news comes just two days after the London Stock Exchange rejected a £2.43 billion takeover approach from US exchange Nasdaq.
The group turned down the 950p-a-share offer from the tech-heavy Nasdaq claiming it "substantially" undervalued the company, and offered investors only an eight per cent premium on the current value of its shares.
Meanwhile, it was suggested the Nasdaq was considering approaching shareholders directly, and may even increase its offer to £10 a share. There were also claims that the LSE's institutional shareholders were coming in behind the Nasdaq bid.
Pan-European exchange operator Euronext was said to be thinking of offering a fresh challenge for the group, although some pundits reckoned it would now walk away from the contest. n There is again talk that Macquarie - owner of the M6 Toll and a stakeholder in Birmingham International Airport - could make a takeover offer for British airports operator BAA.
Macquarie was in talks with US private equity group Blackstone and Canada's Ontario Teachers' Pension Plan but discussions were at an early stage and a bid may still not go ahead, a source said.