Israel joined the international effort to trace more than 200 schoolgirls kidnapped by Islamist militants in Nigeria but Washington said US troops would stay out of any rescue mission.
Nigeria's President Goodluck Jonathan spoke to Israeli Prime Minister Benjamin Netanyahu yesterday over telephone and accepted an offer for assistance in finding the girls, who were kidnapped by Boko Haram fighters nearly a month ago.
Britain, the United States and France have already sent specialist teams and equipment to help Nigeria's military in the search, which is concentrated in the remote northeast riven by five years of deadly violence.
Jonathan's spokesman Reuben Abati said the president told Netanyahu that "Nigeria would be pleased to have Israel's globally acknowledged anti-terrorism expertise deployed to support its ongoing operations".
French President Francois Hollande, meanwhile, said on a visit to Azerbaijan that a summit on security in west Africa focusing on Boko Haram could be held as early as this Saturday "if the countries agree".
The government in Abuja was criticised as slow to respond to find the girls and Amnesty International claimed on Friday that the military had prior warning about the impending abduction.
But it has been forced into action after a groundswell of national and international outrage that has included protest marches across the world.
US, British and French help involves the deployment of military intelligence and surveillance specialists. China has also offered help.
Washington, however, maintained that its assistance did not extend to troops.
"There's no intention, at this point, to (put) American boots on the ground," Hagel told ABC television, admitting that finding the 223 girls still missing would be no easy task.
Jonathan has said he believes the girls were still in Nigeria and searches were being conducted in the Sambisa forest area of northeastern Borno state, where the military has previously found Boko Haram camps and arms caches.
There have been fears, however, that the girls may have been moved across the border into Chad and Cameroon.