Russia's President Vladimir Putin called for an "immediate cessation of military activities" in Yemen in phone conversations with Iran's President Hassan Rouhani, the Kremlin said in a statement on Thursday.

Iranian-backed Shi'ite Houthi militias have seized large parts of Yemen. The conflict deepened on Thursday when warplanes from Sunni Muslim power Saudi Arabia attacked Houthi positions in Yemen, drawing protests from Tehran.

Putin and Rouhani also discussed six-power negotiations over Iran's nuclear programme, expressing hopes for a successful outcome to talks in Lausanne, the Kremlin statement said.