By Edmund Blair TEHRAN, Aug 8 (Reuters) - Iraqi Prime Minister Nuri al-Maliki arrived in Iran on Wednesday for talks on shoring up security in Iraq where his government is crumbling and facing U.S. criticism for not doing enough to reconcile the nation. Maliki's spokesman Ali al-Dabbagh had said before the prime minister's arrival that security would be "a priority" in Iran, which has become an important political player in Iraq following the 2003 U.S. invasion. Iranian media said other economic and political issues would also be discussed. The Shi'ite-led Iraqi government is under pressure to reach a power sharing deal with the country's divided sects ahead of a report in September by the U.S. military and ambassador on Washington's strategy in Iraq. Maliki's visit comes two days after Iraqi, Iranian and U.S. officials held the first meeting of a committee aimed at improving cooperation on stabilising the country. That committee was formed after groundbreaking talks in May and July, also in Baghdad, between Washington and Tehran, the most high-profile meetings between two foes which have not had diplomtic ties since shortly after Iran's 1979 revolution. The United States accuses Iran of stoking violence in Iraq, while Tehran dismisses such accusations and blames U.S. troops for the bloodshed. Iraqi officials have in the past urged both countries not to fight out differences on Iraqi soil. Analysts say both Tehran and Washington have an interest in helping Maliki's government restore calm. Shi'ite Muslim Iran, which analysts say has some powerful friends among Iraq's leading political factions, wants a stable neighbour with a Shi'ite government in power friendly to Tehran. For Washington, a secure Iraq could help hasten a withdrawal. Alaeddin Boroujerdi, head of the Iranian parliament's foreign affairs and national security committee, said before Maliki's arrival that Iran's agreement to the tripartite talks was "the greatest step taken by Iran to help resolve Iraq's current problems", the official IRNA news agency reported. PLUNGED INTO CRISIS Maliki arrived for talks with Iranian First Vice-President Parviz Davoudi and other senior officials, Fars News Agency reported. Iran's Kargozaran daily said he would sign agreements on "security-related issues". Washington has increased pressure on Iraq's leaders, accusing them of failing to make political progress. U.S. Defense Secretary Robert Gates said on Sunday he was disappointed with the lack of progress on reconciliation by Maliki, whose government has been plunged into crisis with 17 ministers, almost half his cabinet, quitting or boycotting. Maliki flew from Turkey where security also topped the agenda. He pledged, in a joint statement, to crack down on Kurdish rebels who use northern Iraq as a base. Kurdistan Workers Party (PKK) operations have drawn threats from Turkey of military intervention in mainly Kurdish northern Iraq. The visit by Maliki to Iran also coincides with an international security meeting on Iraq in Damascus on Wednesday. That two-day meeting includes Officials from Iraq, the United States, Britain, Iran, Turkey and Jordan. Washington says Syria is allowing fighters and weapons into Iraq. Damascus denies this and says ending instability in Iraq and achieving an "honourable withdrawal" for U.S. forces is in its national interest.