"The acquisition of Lasmo allows us to speed up our production targets. We will beat our 1.5m barrels per day target outlined in the strategic plan for 2003," says Vittorio Mincato, Chief Executive of Eni.

Eni would also win a foothold in oil hotspot Venezuela and the Asian gas market, if the bid is approved by Lasmo's shareholders.

And the deal could generate synergies of about 80m euros (£49.7m) a year, according to Eni's estimates.

Amerada Hess says that it will not revise its original bid..

Lasmo is one of the UK's last remaining independent oil and gas companies, its former rival British Borneo being bought up by Eni in March.

State-owned Eni has substantial gas interests in Europe and oil exploration rights in North Africa.