A Lithuanian farmers' party that previously held only a single seat in parliament scored a surprise victory in Sunday's general election run-off, ousting the governing leftists and trouncing conservative rivals.

The Lithuanian Peasants and Green Union party (LGPU) won the most seats, with 56 in the 141-member parliament, while the conservative Homeland Union took 30 and outgoing ruling Social Democrats 17, state election commission official Elena Masvenaite told AFP Sunday, citing almost full results.