The United States and Turkey on Thursday signed a deal to train and equip Syrian rebel forces, officials said.

“Turkey and the United States signed a document a short time ago on the train-and-equip (program),” Turkish Foreign Minister Mevlut Cavusoglu told reporters, reports AFP.

A US embassy spokesman confirmed that the deal was inked in Ankara by Turkish Foreign Ministry Undersecretary Feridun Sinirlioglu and US ambassador to Turkey John Bass.

The announcement puts an end to months of difficult negotiations between the NATO allies on how to train Syrian rebel forces and which enemy they should focus on.

Turkey, a vocal critic of Syrian President Bashar al-Assad, wants supposedly moderate rebels factions to be trained to battle both the regime in Damascus as well as the Islamic State (ISIS) insurgents who have seized large chunks of territory in Iraq and Syria right up to the Turkish border.

Washington, whose aircraft target ISIS positions in Syria, wants to train the rebel forces as part of its fight against ISIS.

The US government hopes the program can begin by late March, so the first trained rebel forces can be operational by year’s end, according to the Pentagon.

The goal is to train more than 5,000 Syrians in the first year of the program.

Doubts remain among some as to whether the equipment and training won’t actually end up aiding radical Islamist rebels, as has occurred in the past.