Filmmaker Rob Reiner slammed President TrumpDonald John TrumpTed Cruz knocks New York Times for 'stunning' correction on Kavanaugh report US service member killed in Afghanistan Pro-Trump website edited British reality star's picture to show him wearing Trump hat MORE on Thursday, claiming he is “aiding and abetting the enemy” in the "War against Isis" and "Cyberwar against Russia."

“Donald Trump is committing Treason against The United States of America,” Reiner tweeted Thursday. “He is aiding and abetting the enemy in The War against Isis and The Cyberwar against Russia."

"He has turned the world’s oldest Democracy into a wholly owned subsidiary of Vladimir Putin. GOP, WAKE UP!” he added.  

On Friday, Reiner claimed Trump is "mentally unstable" and accused the president of taking steps to "destroy" U.S. independence.

ADVERTISEMENT

"Each day this mentally unstable man takes a step closer to destroying 242 yrs. of self rule. And though Democrats want to be restrained, impeachment is inevitable," he tweeted.

"Then GOP Senators will have to make a choice. Either protect Democracy or continue to enable an ignorant criminal," he added. 

Reiner's comments came one day after Trump declared victory against ISIS in Syria and announced his administration's decision to withdraw troops from the nation.

The announcement drew bipartisan criticism, prompting a group of senators from both parties to send a letter to Trump on Wednesday asking him to reconsider his decision.

“If you decide to follow through with your decision to pull our troops out of Syria, any remnants of ISIS in Syria will surely renew and embolden their efforts in the region," they wrote. 

The senators, including  Lindsey GrahamLindsey Olin GrahamThe Hill's Morning Report - Trump takes 2020 roadshow to New Mexico Bolton exit provokes questions about Trump shift on Iran The 13 Republicans needed to pass gun-control legislation MORE (R-S.C.), Jeanne ShaheenCynthia (Jeanne) Jeanne ShaheenOvernight Defense: Dems grill Trump Army, Air Force picks | House chair subpoenas Trump Afghanistan negotiator | Trump officials release military aid to Ukraine Defense spending bill advances over Democratic wall objections Democrats ramp up calls to investigate NOAA MORE (D-N.H.), Joni ErnstJoni Kay Ernst'Mike Pounce' trends on Twitter after Trump slip at GOP retreat Overnight Energy: Trump administration to repeal waterway protections| House votes to block drilling in Arctic refuge| Administration takes key step to open Alaskan refuge to drilling by end of year Trump administration to repeal waterway protections MORE (R-Iowa), Angus KingAngus Stanley KingOvernight Defense: Dems grill Trump Army, Air Force picks | House chair subpoenas Trump Afghanistan negotiator | Trump officials release military aid to Ukraine Democrats grill Army, Air Force nominees on military funding for border wall Bipartisan panel to issue recommendations for defending US against cyberattacks early next year MORE (I-Maine), Tom CottonThomas (Tom) Bryant Cotton2020 Democrats raise alarm about China's intellectual property theft Bolton returns to political group after exiting administration Meadows, Cotton introduce bill to prevent district judges from blocking federal policy changes MORE (R-Ark.) and Marco RubioMarco Antonio Rubio The 13 Republicans needed to pass gun-control legislation GOP group's ad calls on Graham to push for election security: 'Are you still trying?' Former Massachusetts Gov. Deval Patrick joins CBS News as contributor MORE (R-Fla.), expressed concern that the decision would bolster Russian influence in the region. 

"As you are aware, both Iran and Russia have used the Syrian conflict as a stage to magnify their influence in the region," the senators added. "Any sign of weakness perceived by Iran or Russia will only result in their increased presence in the region and a decrease in the trust of our partners and allies."

Reiner has been a frequent critic of Trump, often taking to Twitter to lambast the president.

Reiner has called for Americans to increase their protests against the president, saying in June that he didn't think there was a "line" that could be crossed when it came to demonstrating against Trump.