U.N. envoy Kofi Annan said Friday that Iran should be involved in efforts to end the escalating violence that has claimed thousands of lives and forced hundreds of thousands of people from their homes.

Annan, the joint U.N.-Arab League envoy, told reporters that he is working to convene a so-called "contact group" meeting on Syria in Geneva on June 30. The United States has vehemently opposed the involvement of Iran, which Russia has demanded. Annan said the composition of the meeting is one of the sticking points that may not be resolved until next week.

"I have made it quite clear that I believe Iran should be part of the solution," the former U.N. secretary general told reporters in Geneva, flanked by Maj. Gen. Robert Mood, the head of the struggling U.N. observer mission in Syria. "If we continue the way we are going and competing with each other, it could lead to destructive competition and everyone will pay the price."