French President Hollande, who hosted the summit, said regional powers had pledged to share intelligence and co-ordinate action against the group.

 

Last month it abducted 223 schoolgirls in north-eastern Nigeria, where it is based. Fresh attacks were reported in Nigeria and Cameroon overnight.

 

Thousands of people have been killed by Boko Haram in recent years.

 

The Paris summit brought together Hollande, Nigerian President Goodluck Jonathan, and their counterparts from Benin, Cameroon, Niger and Chad.  As it opened, Hollande called Boko Haram a "major threat to West and Central Africa", and said it had links with al-Qaeda's North-African arm and "other terrorist organisations".

 

After the meeting, he said participants had agreed on a "global and regional action plan".

 

This included sharing intelligence, monitoring borders and co-ordinating action, including possible operations involving French troops in the region, Mr Hollande said.  President Idriss Deby of Chad said regional powers would "tackle this situation head on" and wage "total war on Boko Haram".  Representatives from the UK, US and EU also took part in the meeting.

 

 Jonathan was due on Friday to visit the town where the girls were seized. However the trip was cancelled for security reasons.

 

Boko Haram released a video earlier this week showing more than 100 of the girls and offering an exchange for prisoners.  The girls, who include Christians and Muslims, were seized on 14 April from their school hostel in the north-east Nigerian town of Chibok in Borno state.

 

President Jonathan has ruled out negotiations over their possible release, officials say.

 

As Saturday's summit began, news of fresh violence emerged.