MOSCOW - Russia called on Monday for Iranian involvement in efforts to end the conflict in Syria, putting it at odds with the United States, and said Foreign Minister Sergei Lavrov would travel to Tehran on Wednesday.Lavrov's discussions will focus on the situation in the Middle East and North Africa, with attention to Syria, and on a June 18-19 meeting in Moscow between global powers and Iran on Tehran's nuclear program, Russia's Foreign Ministry said.Russia is resisting Western and Gulf Arab pressure to take a tougher stance toward Syrian President Bashar Assad, rejecting calls for sanctions and advocating a conference bringing together global and regional powers including Iran. Lavrov intends to discuss the initiative with Iran."Without Iranian participation, the opportunity for constructive international influence on the Syrian issue will not be utilized in full measure," the Foreign Ministry said.Russia says the proposed conference would lend support to Kofi Annan's UN-backed peace plan, whose prospects for success are in doubt after frequent ceasefire violations and two massacres in recent weeks.The United States says it does not believe Iran, Assad's strongest regional ally, is ready to play a constructive role in Syria, where the United Nations says government forces have killed more than 10,000 people since March 2011.US Secretary of State Hillary Clinton said last week it was "hard to imagine inviting a country that is stage-managing the Assad regime's assault on its people."Russia is calling on all nations to use their influence on the Syrian government and on rebels to seek an end to the violence and start of political dialogue, but opposes foreign military or political interference."Spreading the 'Libyan model' on other countries of the Middle East and North Africa that are seized by revolutionary events is impermissible," the Foreign Ministry statement on Lavrov's Iran visit said.The ministry made no direct link between the Syrian crisis and the talks next week in Moscow between six global powers and Iran on Tehran's nuclear work, which Western nations fear is aimed at developing weapons capability. Iran denies that.