President Joe Biden will announce an end Thursday to U.S. support for a grinding five-year Saudi-led military offensive in Yemen that has deepened humanitarian suffering in the Arabian peninsula’s poorest country, national security adviser Jake Sullivan said.

The move would fulfill a campaign pledge by Biden, whose administration plans to pursue diplomacy to end the overall conflict in Yemen.

Biden also is announcing the choice of Timothy Lenderking as special envoy to Yemen as soon as Thursday afternoon, when the president is due to speak at the State Department. A person familiar with the matter confirmed the selection, speaking on condition of anonymity ahead of the announcement. The Gulf-based newspaper The National first reported the pick.

Lenderking has been a deputy assistant secretary of state in the agency’s Middle East section. A career foreign service member, he has served in Saudi Arabia, Kuwait and other countries inside and out of the Middle East.

Saudi Offensive Began in 2015

Saudi Arabia began the offensive in 2015 to counter a Yemeni Houthi faction that had seized territory in Yemen and was launching cross-border missiles at Saudi Arabia.

A Saudi-led air campaign since then has killed numerous civilians, and survivors display fragments showing the bombs to be American-made. The conflict has deepened hunger and poverty in Yemen, and international rights experts say both the Gulf countries and Houthis have committed severe rights abuses.