U.S. President Barack Obama on Thursday said Syria's civil war would not end unless Bashar Assad leaves power, discounting suggestions the Middle Eastern leader could take part in future elections.

"I do not foresee a situation in which we can end the civil war in Syria while Assad remains in power," Obama said on the sidelines of a trade summit in Manila.

Syrian President Bashar Assad said Wednesday his country was not a breeding ground for the Islamic State group, blaming the creation of the jihadist organization on the West.

"I can tell you Daesh doesn't have the natural incubator, social incubator, within Syria," he said in a television interview with Italian national broadcaster Rai, using the Arabic acronym for the IS group.

The United States issued a $5 million reward Wednesday for information leading to the capture of a Saudi-born jihadist accused of smuggling foreign fighters into Syria.

The State Department said that Tirad al-Jarba, known under the nom de guerre Abu Muhammad al-Shimali, is a senior member of the Islamic State extremist group.

President Barack Obama would veto a Republican bill introduced in the wake of the Paris attacks to toughen the screening process for Syrian refugees, the White House said Wednesday.

The U.S. House of Representatives could vote as early as Thursday on resolution 4038, which aims to block administration plans to resettle 10,000 Syrian refugees in the coming year.

A family of Syrian refugees accepted into the United States has been re-routed after the governor of Indiana objected to them coming to his state, officials said Wednesday.

A non-governmental resettlement agency had planned to send the family of three, selected from a U.N. refugee camp in the Middle East and vetted by U.S. security agencies, to start a new life in Indianapolis.

Russia said Wednesday that following the carnage in Paris it was now clear that global powers should unite without any preconditions on the fate of Syria's embattled leader Bashar Assad.

"It seems to me there are no longer any doubts that it is simply unacceptable to put forward any preconditions for joining forces in the fight against terror," Russian Foreign Minister Sergei Lavrov said after meeting his Lebanese counterpart Jebran Bassil in Moscow.

Al-Qaida's Syrian affiliate Al-Nusra Front said it had downed two Russian reconnaissance drones over a military airport it controls in northwest Syria.

If confirmed, the incident would be the first time that the armed opposition down a Russian aircraft since Moscow launched strikes in Syria on September 30.

U.S. President Barack Obama on Wednesday praised Russia's role in talks to end the Syria crisis and offered the prospect of better ties if Moscow focused military strikes on the Islamic State group.

Obama said Russia had been a "constructive partner in Vienna in trying to create a political transition," referring to international talks in Austria.

U.S. Republicans took steps Tuesday aimed at freezing White House programs that resettle Syrian and Iraqi refugees in America, saying they want stricter security measures in place in the wake of the deadly Paris attacks.

House Speaker Paul Ryan called for a "pause" in the Syrian scheme, joining more than half of state governors urging President Barack Obama to suspend the program and fully review the vetting process to ensure that would-be attackers do not slip into the country as refugees.

A Syrian journalist who lives and works in the war-scarred city of Aleppo was awarded the Reporters without Borders Prize in France on Tuesday for her defense of press freedom.

The Paris-based media rights group singled out Zaina Erhaim for her "determination and courage" in covering the conflict in Syria, which is deemed the most dangerous country in the world for journalists.