ISTANBUL (Reuters) - Government aid agencies of the United States and Britain have directed their humanitarian partners to stop using a border crossing between Turkey and Syria, officials said, due to concerns that taxes on aid trucks were used to fund an extremist group.

The United States Agency for International Development (USAID) directed its partners working in northwest Syria to immediately cease all use of the Bab al-Hawa border crossing for USAID-funded awards on Sept. 26, a USAID official said.

USAID had received information that jihadist group Hayat Tahrir al-Sham was likely drawing financial benefits from trucks crossing through the border, the official said.

Likewise, Britain’s Department for International Development (DFID) directed its aid partners to stop using the crossing, a UK government source said, citing concerns that levies were being paid to extremist groups in exchange for allowing aid trucks to pass.

Tahrir al-Sham, the main jihadist group in the Idlib region, is designated a terrorist organisation by the United Nations, the United States and Turkey. Bab al-Hawa is the only official border crossing connecting Turkey to the Idlib region, where an estimated 2.1 million people are in need of humanitarian assistance.

Some 2,284 trucks carrying aid went through the crossing in the first eight months of this year, according to David Swanson of the United Nation’s Office for the Coordination of Humanitarian Affairs (OCHA).

The Bab al-Salama border crossing from Turkey into Aleppo province, also used by USAID partners for humanitarian shipments, will not be impacted, the U.S. official said. Only 428 trucks passed through Bab al-Salama in the first eight months of this year.

The Syrian Salvation Government, an administration set up to run civilian affairs in opposition-held Idlib, on Saturday said the collection of fees on trucks delivering humanitarian aid would be stopped from this month.

But the aid convoys have yet to resume. Britain is currently reviewing its decision, the UK government source said, while the USAID official did not comment on whether the decision is under review following the Salvation Government statement.

“We hope that the convoys with life-saving assistance will be able to resume without delay to avoid any break in supporting the 3 million people who live in the area,” OCHA’s Swanson said.