PORT-AU-PRINCE, Haiti (AP) — The United Nations' top envoy in Haiti pressed the government on Friday to hold overdue legislative and local elections "as soon as possible" this year.

Mariano Fernandez said in a statement that he welcomed a recent agreement between the executive branch and Parliament to form an electoral body but that Haitian authorities need to quickly instal its required nine members.

Prime Minister Laurent Lamothe said he agreed with the UN official.

"We want the same and have taken many steps to that end," Lamothe wrote in a text message to The Associated Press.

"We want elections this year as well."

The vote was supposed to have been held in late 2011. But it's been delayed because Haitian authorities haven't been able to agree on the composition of the electoral body.

The election is for 10 vacant seats in the 30-member Senate, or one-third of the Upper Chamber, and for hundreds of seats at the local level.

It will be the most complex election organised in Haiti since 2006, and some 35,000 candidates are expected to run, according to the UN.