Syrian President Bashar Assad has ruled out any foreign solution to his country's crisis.
He told Iranian TV his government had a duty to "eliminate terrorists" to protect its people.
The interview comes amid escalating violence inside Syria and increasing tensions with Turkey as Ankara mobilizes forces on its border with Syria after Assad's forces shot down one of its military jets last week.
A key international meeting is set for Geneva on June 30 in a fresh bid to end the 16-month-old crisis.
The meeting has been called by the international envoy for Syria, Kofi Annan, who is expected to present a transition plan to open the way for a unity government in Syria.
Among those attending the Action Group meeting are the five permanent members of the Security Council, the EU, as well as Iraq and Turkey. Iran and Saudi Arabia will not be attending.
Iran has expressed disappointment over the perceived snub, offering to play a mediating role in Syria.
UN Secretary-General Ban Ki-moon said Annan would inform Iran on the outcome of the Geneva talks.
Moscow reportedly objects to wording in Annan's transition plan which could be interpreted to mean Assad could not serve in a national unity government.
Diplomats at the UN say Russia has proposed dropping language on excluding people from a Syrian national unity government.
Diplomats say officials from the United States, Britain, and France have rejected the Russian proposal.
The matter is expected to be raised during talks between Russian Foreign Minister Sergei Lavrov and U.S. Secretary of State Hillary Clinton in the northern Russian city of St. Petersburg on June 29.
Based on reporting by AP, AFP, and Reuters