Afghanistan, March 7 -- The United Nations says it is preparing to support thousands of Afghan returnees from Iran as humanitarian challenges grow amid border tensions.

George Gagnon, acting head of the United Nations Assistance Mission in Afghanistan (UNAMA), says the UN is preparing to support Afghan returnees from Iran.

The UN said Saturday that agencies including the International Organization for Migration and the United Nations High Commissioner for Refugees will assist returnees at border crossings.

These agencies will also provide support to communities hosting the returnees as more Afghans continue to return to the country.

Gagnon said clashes between the Taliban and Pakistan have complicated humanitarian operations and made ai...