BBC News with Jonathan Wheatley

West African leaders have warned the incumbent President of Ivory Coast, Laurent Gbagbo, that force will be used if he doesn't step down. The statement was issued after an emergency summit in Nigeria of the regional group Ecowas. John James reports from Abidjan.

The international pressure on Mr Gbagbo to leave office has stepped up a few

notch

es in the last 24 hours, but in a

communique

read on state television he remains defiant. If he rejects the final chance offered by West Africa's regional bloc Ecowas to hand over power peacefully, then he faces a very real risk of military

intervention

, almost certainly led by Nigeria. Army chiefs in the region will be instructed to start planning. Several hours earlier, the man Ecowas recognised as the winner of last month's poll, Alassane Ouattara, appealed to the Ivorian army to play a republican role and to protect the civilian population against armed attacks.

France has confirmed that Russia is to buy at least two French warships. The Mistral-class assault vessels can carry up to 16 helicopters and will be the first such purchase by Russia from a Nato member country. The deal has caused unease in other Nato countries, especially the United States. Marcus George reports.

The statement from the office of the French President Nicolas Sarkozy announced that a French consortium had been selected to supply the Russian navy with two Mistral-class warships. The consortium will work with a Russian naval yard to build what are known as projection and command vessels, with the possibility of two more to follow.