The US says it will give $5m (£3.2m) towards a multi-national task force being set up to fight Nigeria’s militant Islamist group Boko Haram.
Boko Haram “was not just a Nigerian problem”, US official Linda Thomas-Greenfield said.
The group was blamed for suicide bombings which killed more than 20 people in neighbouring Chad on Monday. Chad will be the headquarters of the Nigeria-led force of around 7,500 troops from five countries.
The formation of the force has gained momentum since Nigeria’s President Muhammadu Buhari took office last month.
Nigeria’s previous administration, led by Goodluck Jonathan, was seen to have dragged its heels over the creation of the force, as it feared it would undermine Nigeria’s sovereignty, correspondents say.
The US also turned down a request by Jonathan’s administration last year to sell it weapons because of the poor human rights record of its military.
The issue led to a diplomatic row, with Nigeria accusing the US of refusing to help land a “killer punch” against Boko Haram.
Ms Thomas-Greenfield, the US assistant secretary of state for Africa, said the US was in talks with Buhari’s government on how it could assist more in the campaign against the militants.
It comes after President Buhari’s visit last week to the G7 summit in Germany where he said Nigeria would welcome more international support in the struggle with the jihadists.
The multi-national force is expected to be made up of troops from Nigeria, Niger, Chad, Cameroon and Benin.
Chad, Cameroon and Niger have been helping Nigeria recapture territory from Boko Haram, but their activities have so far been largely uncoordinated.
The African Union (AU) backed the creation of a multi-national force in January, saying Boko Haram required a “collective, effective and decisive response”.
Boko Haram’s six-year insurgency has left some 13,000 people dead and 1.5 million homeless, rights groups say.
The group has pledged allegiance to Islamic State, which is fighting to establish a global caliphate.