Vice President Mike Pence convinced Director of National Intelligence Dan Coats not to resign late last year amid ongoing frustrations with the Trump administration, according to a new report.

Coats and Trump have been at odds throughout the latter’s presidency. Tensions culminated in December when Trump abruptly decided to withdraw all U.S. troops from Syria and then-Defense Secretary James Mattis left the administration over the decision.

Pence convinced his longtime friend Coats — a former Republican congressman and senator from Indiana — to stay in the intelligence post at least until the summer, according to NBC News. The vice president has also encouraged Trump not to get rid of Coats, whom the president privately refers to as “Mister Rogers.”

Tensions have simmered between the two since Coats was confirmed as intelligence chief.

Trump has pressured Coats to find proof that former President Barack Obama wiretapped him during the 2016 campaign. Coats repeatedly told the president that he was not wiretapped, but the president disagreed.

In July, during a live televised interview, Coats appeared to mock Trump when news broke that the president had invited Russian President Vladimir Putin to Washington, D.C. Pence mediated the situation and Coats personally apologized to Trump.

Trump has also pushed Coats to publicly criticize the U.S. intelligence community, and has accused him of leaking classified information.

The Washington Post reported last month that Trump has expressed frustration with Coats, calling him “not loyal.”

“I am focused on doing my job, and it is frustrating to repeatedly be asked to respond to anonymous sources and unsubstantiated, often false rumors that undercut the critical work of the Intelligence Community and its relationship with the President. I am proud to lead an IC singularly focused on the vital mission of providing timely and unbiased intelligence to President Trump, Vice President Pence and the national security team in support of our nation’s security,” Coats said in a statement to NBC News.