(Adds reaction from Burkina Faso in paragraph 3)

Jan 2 (Reuters) - The United States has dropped Burkina Faso from its AGOA trade preference program citing deep concerns over "unconstitutional change" in government in the West African country, the U.S. Trade Representative's (USTR) office said on Sunday.

Frustrations over the government's inability to curb an Islamist insurgency spurred two military coups in Burkina Faso in 2022. Both the previous and current juntas have made efforts to beef up security, but Islamist attacks have continued.

The junta's foreign affairs ministry reacted to the U.S. decision on Monday by repeating a November statement saying that the timetable for a return to democracy had not changed.

Burkina Faso had committed to return to constitutional rule in 24 months in a July agreement with West African regional bloc ECOWAS.

The U.S. African Growth and Opportunity Act (AGOA) provides sub-Saharan African nations with duty-free access to the United States if they meet certain eligibility requirements, such as eliminating barriers to U.S. trade and investment and making progress toward political pluralism.

The USTR's office said Burkina Faso had failed to meet the requirements of the AGOA statute and would be given "clear benchmarks" for a pathway toward reinstatement to the trade program, adding that Washington would work with the Burkinabe government.

Burkina Faso is one of the world's poorest countries. Militants linked to al Qaeda and Islamic State have killed thousands of civilians there, creating one of Africa's fastest-growing humanitarian crises.

Nearly 2 million people have been displaced and reside in makeshift camps, many run by the United Nations, that dot the arid countryside.

Just before Christmas, Burkina Faso's military government ordered a senior United Nations official to leave the country, a decision that was contested by the U.N..

Although the government did not give a reason at the time, its foreign minister later accused the official, Barbara Manzi, of painting a negative picture of the security situation in the country. (Reporting by Ismail Shakil in Ottawa and Thiam Ndiaga in Ouagadougou; Editing by Estelle Shirbon)