Michael McFaul, a former U.S. ambassador to Russia, blasted Republican presidential nominee Donald Trump Donald John TrumpBubba Wallace to be driver of Michael Jordan, Denny Hamlin NASCAR team Graham: GOP will confirm Trump's Supreme Court nominee before the election Southwest Airlines, unions call for six-month extension of government aid MORE on Twitter Friday for saying that Russian President Vladimir Putin has been a better leader than President Obama.

Trump and his running mate Mike Pence Michael (Mike) Richard PenceGardner signals support for taking up Supreme Court nominee this year Biden leads Trump by 12 points among Catholic voters: poll GOP brushes back charges of hypocrisy in Supreme Court fight MORE praised the Russian leader as "stronger" than Obama, citing his polled approval rating as evidence.

If Obama seized control of Fox, allowed only supporters in Congress, closed the NRA & arrested Trump, he too might have 80% approval rating — Michael McFaul (@McFaul) September 9, 2016

McFaul, who served as the ambassador in Moscow from 2012 to 2014, also slammed Trump for fawning over an authoritarian leader.

In praising Putin, Trump conflates "strong leader" with autocratic rule. Imagine earlier presidents doing that in Cold War or interwar eras? — Michael McFaul (@McFaul) September 9, 2016

The former ambassador has been an outspoken critic of the real estate mogul, arguing that a Trump presidency would be in the Kremlin’s best interest.

Trump has struggled to put to bed claims that his campaign is too close to Russia's interests, criticism that found new life Thursday evening, when he gave an interview on a TV station owned by the Russian government.