Saudi Arabia's execution of prominent Saudi Shia cleric Nimr al-Nimr serves the interests of Islamic State militant group (ISIS), a prominent Iraqi lawmaker with ties to Iran said on Saturday in a statement condemning the act.

"The execution of Sheikh al-Nimr is a service to Daesh, which is betting on expanding by igniting sectarian wars," said Humam Hamoudi, a prominent Shia politician and member of the powerful Islamic Supreme Council of Iraq (ISCI) party.