DAKAR, Senegal (AP) — The United Nations secretary-general says a takeover by Gambia's security forces of the country's electoral commission offices could compromise "sensitive electoral material" as the president refuses to accept being voted out of power.

The spokesman for the U.N. chief in a statement Wednesday said Tuesday's blockading of the election offices was an "outrageous act of disrespect" and a sign of defiance as West African leaders visited to urge President Yahya Jammeh to accept his loss.

The U.N. statement calls on security forces to immediately leave the electoral offices. It also calls for a peaceful transfer of power.

West African leaders will meet Saturday about Gambia's election crisis. Jammeh initially conceded to Adama Barrow, who won the Dec. 1 vote, but later rejected the results.

Jammeh's party wants a new election.