The Trump administration is intensifying its strategy to compel Russia to drop its support of the Assad regime in Syria, according to a State Department official.

Much of that effort involves public pressure, as the State Department released surveillance photos Monday officials said showed a probable crematorium at the Saydnaya military prison.

"We call upon Russia to use its influence with the Assad regime to get it to adhere to a lasting negotiated ceasefire,” said Heather Nauert, the State Department spokesperson, as she opened a presentation of those surveillance photos. “That ceasefire, we believe, will reduce violence and also ensure unhindered humanitarian access and stop the indiscriminate killings of civilians.”

SYRIAN REGIME USING CREMATORIUM TO 'COVER UP' MASS MURDERS, STATE DEPARTMENT SAYS

The Saydnaya facility is about a 45-minute drive north of Damascus. A building on the western end of the complex shows melted snow, evidence of heat from what is probably a crematorium, said the State Department. However, officials acknowledged they cannot determine that for certain.

The Syrian government regime, according to state media, said the charges are baseless and a “Hollywood story.”

The administration also cited reports from Amnesty International claiming the Assad regime executed from 5,000 and 13,000 people between 2011 and 2015. The Assad regime built the suspected crematorium to cover up its mass murder, according to officials.

"They are upping the ante with the Russians," said Ambassador William Courtney of the RAND Corporation, of the administration’s pressure campaign against Russia. “This is a pretty significant ramp up in great part because people remember the Holocaust and World War II and so the idea of a crematorium to destroy bodies will cause a pretty negative reaction.”

SYRIA 'CATEGORICALLY' DENIES US ACCUSATIONS OF MASS KILLINGS

Last month, the administration took a similar approach when it charged the Assad regime attacked a rebel-held Syrian town, Khan Sheikhoun. As Russia previously agreed to oversee the destruction of Syria’s chemical weapons, U.S. Secretary of State Rex Tillerson then said Russia was complicit or incompetent.

Even with the increased public pressure, analysts said convincing Russia to drop its support of Assad will be difficult.

"Pressuring Russia is an important step, obviously Russia is a belligerent in this conflict, Russia is actually likely committing what amounts to war crimes of its own,” Jennifer Cafarella, the lead intelligence planner at the Institute for the Study of War. “I do think it's important that President Trump is taking that step, but naming and shaming Russia for its role in Syria is not going to be sufficient in my estimation to force Russia to change."

UN SUSPECTS CRUEL TREATMENT IN SYRIAN PRISONS

“Relations between the West and Russia are so poor now that even though they have some common long-term interests,” said Courtney. “It's pretty difficult to move forward.”

The U.S. is also pressing Assad without Russia. The Treasury department announced Tuesday expanded economic sanctions to several individuals and entities connected to the Assad regime. The sanctions can freeze assets and prevent Americans from conducting business with those designated.

The United Nations is also trying, again, to develop a sustainable ceasefire in Syria. Diplomats met Tuesday in Geneva to discuss establishing a new Syrian constitution and elections. The five previous rounds made little progress and Assad dismissed these discussions as irrelevant.