French construction group Vinci declined to comment last night on whether it planned to continue with its £516 million sterling (€826 million) bid for British regional airports operator TBI, owner of Belfast International Airport in Northern Ireland.

But the group is today expected to formally abandon the bid. Vinci failed to obtain the 90 per cent acceptances that would have forced it to proceed with the 90p-a-share cash bid at the first closing date yesterday.

Shareholders representing just over 70 per cent of shares were able to accept the bid in time for the first closing date, which came just over two trading days after the TBI board recommended the Vinci offer.

The level of acceptances allows Vinci to let its offer lapse without making a representation to the Takeover Panel that the US terrorist attacks had resulted in a "material adverse change" in TBI's business.

It is understood that Vinci came to its decision because it believes 90p a share is no longer the correct value for TBI given the impact of the terrorist attacks on the airline and the airport industry.

Although TBI first rejected the bid it believes that given the current market uncertainty following the recent terrorist attacks the offer is now "fair and reasonable". Vinci launched its bid for TBI last month, following a profit warning from the regional airport operator.

In addition to Belfast International, TBI owns Cardiff Airport and has a majority stake in Luton.