The United States and Turkey have signed an agreement to train and equip moderate Syrian opposition fighters.

The agreement states that Ankara will provide an equal number of trainers to work alongside their American military counterparts, a U. official said on Thursday.

The deal with Turkey formalised plans for one of four known sites to be used in a broader programme to train Syrian rebels opposed to the Islamic State of Iraq and the Levant (ISIL) group.

A deal for a facility in Jordan is imminent and locations in Saudi Arabia and Qatar could be ready in a few months, the US official said.

The effort to train and equip Syrian moderates to fight ISIL began to pick up steam after months of planning.

'Moderates identified'

The Pentagon said on Wednesday it had identified some 1,200 Syrian opposition fighters for potential training.

The US-Turkey deal was signed by an undersecretary at the Foreign Ministry and the US ambassador, a Turkish Foreign Ministry official said.

It provides a training facility that will require only modest security upgrades, work Ankara has already begun, an official at the US military's Central Command told reporters.

"The site that they have offered is a brand new facility. It is one that we would be proud to call our own," said the US official, who spoke on condition of anonymity.

The official said the training site Jordan planned to provide also was new and ready to use.

"We're working through some final technical agreements with them (Jordan) that we anticipate being signed any day, if it has not already been signed," the official said.

A site offered by Saudi Arabia will be ready for use within 30 to 90 days, "so it will come into the picture shortly after Jordan and Turkey," the official said.

A site offered by Qatar could be ready within six to nine months, he said.

The US official said Turkey demanded an equal role in the training mission and would provide the same number of trainers at its facility as the American side.

US officials have said they plan to train about 5,000 Syrian fighters a year for three years under the programme, which is due to begin in March.

Turkey hopes the training will also bolster the weakened and divided Syrian opposition in their war against Syrian President Bashar al-Assad.