Former US ambassador to Russia blasts Trump's Putin praise

Michael McFaul, a former U.S. ambassador to Russia, blasted Republican presidential nominee Donald TrumpDonald John TrumpLiz Cheney: 'Send her back' chant 'inappropriate' but not about race, gender Booker: Trump is 'worse than a racist' Top Democrat insists country hasn't moved on from Mueller 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 PenceMichael (Mike) Richard PenceApollo 11 reminds America what unity really means Trump steps up attacks on 'Squad' after post-rally furor Trump is missing an opportunity in Hong Kong MORE praised the Russian leader as "stronger" than Obama, citing his polled approval rating as evidence.

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

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.