Saudi Arabia's foreign minister said Tuesday there is a military option in Syria that will end with the removal of President Bashar Assad if the preferred political option does not lead to his departure.

Adel Al-Jubeir told a small group of journalists the military option could be lengthier and more destructive, but the choice is entirely up to Assad and whether he accepts the political roadmap agreed to by key nations in 2012. That deal would have him hand power to a transitional government.

The Saudi minister would not say what Western and Arab opponents of Assad's regime may or may not do to counter the new military buildup in Syria by Russia, Assad's closest ally along with Iran. "We're not talking about" it, he said.

But Al-Jubeir said the Free Syrian Army and moderate opposition forces are fighting against Assad and receiving support from a number of countries and that "will be intensified."

U.S. President Barack Obama has said he is willing to talk to Russia and Iran about how to end the Syrian conflict, now in its fifth year with more than 250,000 people killed and millions displaced and fleeing the country. Russia and Turkey have proposed a meeting that would include the United States, Russia, Saudi Arabia, Iran and Turkey. The United States has insisted Assad must leave power.

Al-Jubeir said Saudi Arabia hasn't said "no" to sitting down with the Iranians. But he called Iran "an occupying force in Syria" and said it cannot be part of the solution until it withdraws its forces from Syria, as well as the Hezbollah fighters and other Shiite militias that it sent to the country to support the Assad regime.

The Saudi minister said the political roadmap based on the 2012 Geneva agreement included a governing council composed of elements of the existing government and the opposition would assume executive power — leaving Assad aside — to work on maintaining state institutions, drafting a new constitution, and holding elections to form a new government.

"Sometime between the formation of this council and elections, the theory of this is that — whether it's a day or a week or a month, I don't know — Assad would sail into the sunset," Al-Jubeir said.

"If Bashar Assad accepts the political process where he transitions out of the country, I think we can get somewhere," Al-Jubeir said, "but we haven't seen any indication that he would do this, nor have we seen any indication that his two main supporters, Russia and Iran, are prepared to push him in that direction. So while we hope that the process will succeed, I believe, given the position of Russia and Iran, our hope is not that great."

Al-Jubeir dismissed widespread belief that Sunni-dominated Saudi Arabia is in an intense battle with Shiite Iran to be the dominant power in the Middle East.

"We've been living in the Middle East all our lives," he said. "We're not the ones meddling in the affairs of other countries. The Iranians are. So you should look at it as Iranian aggression against other countries in the region."

Al-Jubeir added that if the Russians were serious about fighting Islamic State extremists known as Daesh, who control large regions of Syria, "they could join the existing international coalition."

"But for them to go out and insert forces into Syria, which is the first time that the Russians have done so in decades, is a big step, and is an indication that their objective may be to prop up the Assad regime, more than it is to fight Daesh," he said.

Al-Jubeir implicitly criticized the U.S. and other opponents of the Assad regime for sparking the current exodus of thousands of Syrians to Europe to escape the conflict. He said Saudi Arabia was calling early on for a no-fly zone and robust arming of the Syrian opposition, and if this had been done early on, "we would not be in this situation."