Beirut: A senior US diplomat has arrived unexpectedly in Beirut for talks on the political deadlock that has left Lebanon without a president for nearly five months.

Lebanon's sharply divided parliament has failed to elect Army commander General Michel Suleiman as a consensus president because the US-backed parliamentary majority and the Syrian-backed opposition remain at loggerheads over power-sharing and the shape of the future Cabinet.

US Assistant Secretary of State for Near Eastern Affairs David Welch met shortly after his arrival with officials from the anti-Syrian parliamentary majority.