BEIRUT – International envoy Kofi Annan tried to rescue his peace plan for Syria by seeking help Monday from Iran, a staunch ally and military backer of President Bashar Assad’s regime.

Before flying to Tehran, Annan said he had agreed on a new approach with Assad to stop the violence, which activists say has killed more than 17,000 people since the conflict began in March 2011.

Annan did not spell out the agreement or say what kind of involvement he saw for Iran in resolving the crisis. Anti-regime fighters dismissed any role for Iran in a plan they and some experts said has little hope of succeeding.