The statement from Ali Akbar Velayati, a senior adviser to Iran's Supreme Leader Ayatollah Ali Khamenei, came in the wake of his meeting in Moscow with Russian President Vladimir Putin. A day earlier, Israeli Prime Minister Benjamin Netanyahu told Putin that Israel wants Iran to leave Syria.
The high-level talks precede Monday's summit in Helsinki between Putin and U.S. President Donald Trump, who are set to discuss the Iranian presence in Syria.
Both the U.S. and Israel want Iran to pull out of Syria, while Russia has warned it would be unrealistic to expect Iran to fully withdraw from the country.
A possible deal could see Syrian troops replacing Iranian forces and its proxy Hezbollah militia in the areas near the Israeli-occupied Golan Heights.
Velayati reaffirmed Iran's firm intention to maintain its presence in Syria, but skirted a question about a possible pullback from the border, saying only that Tehran won't bow to U.S. and Israeli coercion.
"We coordinate the Iranian presence in Syria with Russia and Syria," Velayati said during a meeting at Moscow's Valdai Club discussion platform. "We will be present there the way we consider necessary. Sometimes we will play our role in Syria open-handed, sometimes we will do it with our hands hidden."
While Velayati maintained a combative tone, his careful response reflected the intense diplomatic maneuvering ahead of the Helsinki summit.
He expressed skepticism about the outcome of the meeting, repeating tough criticism of the U.S. and saying he didn't expect Trump to make any positive contribution to stabilizing the Middle East.
Velayati argued that Iran along with Russia helped stem fighting in Syria and prevented the country from falling to the Islamic State group and other militants, scoffing at the U.S. demands to leave.
"We have come there without the Americans' permission and we won't heed their demands to leave," he said.
Velayati also strongly warned Russia against listening to the U.S. arguments about the Iranian presence in Syria.
"I told the Russian officials: Now the Americans are telling you that the Iranians must leave Syria and tomorrow they will ask you what you are doing in Syria," he said. "They are trying to split our alliance."
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