Secretary of State John Kerry said Russia has proposed military-to-military talks with the U.S. on Syria, according to an Associated Press news alert Wednesday.

On Tuesday, Kerry had his third phone call in 10 days with Russian Foreign Minister Sergey Lavrov on Russia's intentions in the region, according to the State Department.

"Kerry made clear that Russia's continued support for [Syria's] President Assad risks exacerbating and extending the conflict, and undermining our shared goal of fighting extremism if we do not also remain focused on finding a solution to the conflict in Syria via a genuine political transition," the department said in a statement.

Russia has sent weapons, portable housing units, military advisors, artillery, and about a half dozen tanks plus air support near the port city of Latakia, a stronghold of Assad. A Pentagon spokesman described the build-up Monday as an apparent Russian "forward operating base."

Putin defended Russia's military support in Syria Tuesday, saying that Russian weapons were needed to defeat the Islamic State's "terrorist aggression."

"We support the government of Syria in its opposition to terrorist aggression," Putin said in Dushanbe, the capital of Tajikistan, the Washington Post reported. "We have provided and will provide necessary military and technical support and call on other nations to join us."

The United Nations is currently investigating whether Assad used chemical weapons against his own people in an ongoing, brutal five-year civil war that has displaced 4 million Syrians and led to a refugee crisis in Europe. The Syrian city of Al-Raqqa is the de-facto capital of the Islamic State.

Without naming any specific measures that would be taken, State Department spokesman John Kirby said Tuesday, "These actions inside Syria could very well lead to further isolation for Russia."

The Obama administration may not lay out a course of action to take with Russia until its motives become clearer. "The decision-making process in that country is rather opaque," White House spokesman Josh Earnest said of Russia.

The United States has been committed to regime change in Syria, and Russia's continued support for Assad has flummoxed the Obama administration. It continues to be committed to arming "moderate" Syrian rebels but has had difficulty finding recruits that meet the criteria.

Russia wants Syria talks http://washex.am/1Knj1A6 in White House on LockerDome