Former House Speaker John Boehner. Thomson Reuters

Former House Speaker John Boehner on Wednesday said that aside from foreign affairs, President Donald Trump's performance in office has been a "complete disaster."

While Boehner gave Trump high marks on foreign policy and international affairs, "everything else he’s done [in office] has been a complete disaster," Boehner said at KPMG's Global Energy Conference, as reported by the energy publication Rigzone.

"He’s still learning how to be president," Boehner added.

Boehner said that while Trump has been a close friend and golf buddy of his for 15 years, he never "envisioned" him being president.

In terms of the ongoing investigation into Russia's involvement in the 2016 election, Boehner warned his "crazy left wing Democratic colleagues" that talk of Trump's impeachment is the "best way to rile up Trump supporters."

"Remember, impeachment is not a legal process; it’s a political process," Boehner said. For impeachment to occur, the House majority leader, California Rep. Kevin McCarthy, would have to trigger the process. McCarthy, however, said he has 100% confidence in Trump after he joked that the president was on Putin's payroll during a meeting in June.

Boehner, for his part, dismissed any notion that he would run for the presidency in the future.

"I drink red wine. I smoke cigarettes. I golf. I cut my own grass. I iron my own clothes," Boehner said. "And I’m not willing to give all that up to be president."

"I wake up every day, drink my morning coffee and say hallelujah, hallelujah, hallelujah," Boehner added.