Independent Vermont Sen. Bernie Sanders’ 2016 campaign spokesman criticized former Secretary of State Hillary Clinton and her team Monday, responding to former Clinton staffers revealing that Sanders demanded to fly private while campaigning for her in 2016.

“You can see why she’s one of the most disliked politicians in America, she’s not nice. Her people are not nice,” Michael Briggs told Politico. “[Sanders] busted his tail to fly all over the country to talk about why it made sense to elect Hillary Clinton and the thanks that [we] get is this kind of petty stupid sniping a couple years after the fact.” (RELATED: Bernie Sanders, Climate Hawk, Spends Nearly $300K On Private Jet Travel In A Month)

“It doesn’t make me feel good to feel this way but they’re some of the biggest assholes in American politics,” he added.

Sanders agreed to campaign on Clinton’s behalf in 2016 after he lost the Democratic primary to her. He reportedly requested that the Clinton campaign charter private jets to get him to rallies, costing about $100,000 in total in the last two months prior to the election.

Multiple former Clinton staffers reportedly labeled Sanders’ demand to fly privately unnecessary.

Sanders frequently criticizes wealthy individuals for not flying commercially because there’s additional carbon emissions produced. When he announced his 2020 presidential campaign earlier this month, he specifically called out the fossil fuel industries for contributing to climate change.

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