The US military is planning to deploy more than 400 troops to help train Syrian militants to fight the Takfiri group ISIL, along with hundreds of US support personnel.

The US military is planning to deploy more than 400 troops to help train Syrian militants to fight the Takfiri group ISIL, along with hundreds of US support personnel.

Turkey, Qatar and Saudi Arabia have offered to host the training expected to begin in the spring, Colonel Steve Warren, a Pentagon spokesman, revealed on Thursday.

Warren did not identify where they will draw the forces from for the training mission or offer additional details on the troop figures, first reported by Defense One website.

The training program is a part of President Barack Obama's multi-year plan to field “local forces” in Syria to halt and eventually roll back ISIL militants, while pounding them with US-led airstrikes.

The Pentagon has estimated that it can train more than 5,000 recruits in the first year and that up to 15,000 will be needed to retake areas of eastern Syria controlled by ISIL.

Meanwhile across the border in Iraq, Obama has authorized more than 3,000 US troops to advice and train Iraqi and Kurdish forces.

The disclosure of the planned troop deployments for the Syria training mission came just days after senior US officials met Syrian opposition and civil society leaders in Istanbul to discuss the program.

US Major General Michael Nagata, Combined Joint Interagency Task Force - Syria Director, and US Special Envoy for Syria Daniel Rubinstein led the meeting on the US side.

'These introductory meetings were an important step as we prepare to launch the train-and-equip program later this spring with our international partners,' said Pentagon spokeswoman Commander Elissa Smith.