WASHINGTON (AP) — Oh, that dreaded open microphone!

Republican Sen. Susan Collins got caught Tuesday at the end of a hearing with a microphone that was still hot — and captured her ripping President Donald Trump and making fun of a fellow lawmaker who had been critical of her on health care.

Collins, a moderate from Maine, can be overheard complaining about Trump and his proposed 2018 budget, which slashes spending with deep cuts to domestic agencies, food stamps, Medicaid, highway funding and medical research.

"Whenever there was a grant, they just X-ed it out, with no metric, no thinking about it, no nothing," she tells Democratic Sen. Jack Reed of Rhode Island. "It's just incredibly irresponsible."

"I think he's crazy," Reed says. And Collins adds, "I'm worried."

Collins was also snagged making unflattering remarks about Rep. Blake Farenthold, R-Texas, a day after he blamed "some female senators from the Northeast" for blocking health care legislation. He said he wished he could challenge them to a duel "Aaron Burr-style."

"Did you see the one who challenged me to a duel?" Collins asks.

"I know," Reed replies. "Trust me. Do you know why he challenged you to a duel? 'Cause you could beat the s--- out of him."

Collins continues, "I don't mean to be unkind but he's so unattractive it's unbelievable."

Collins then mentions a widely circulated picture of Farenthold wearing baby blue pajamas with yellow ducks on them as he poses in the photo with a big grin next to a scantily clad young woman.

The audio followed a meeting of the Senate Appropriations Subcommittee on Transportation, Housing and Urban Development. Collins is the chairman of the committee and Reed is the ranking Democrat on the panel.

Farenthold's office declined to comment, but Collins said she had received an apology from the congressman, and offered one in return.

"Neither weapons nor inappropriate words are the right way to resolve legislative disputes," Collins said in a statement. "I received a handwritten apology from Rep. Farenthold late this morning. I accept his apology, and I offer him mine."

Reed's office said he was just "letting Sen. Collins know he's in her corner."

He has said it publicly and privately, Reed's spokesman, Chip Unruh, said in a statement: "the Trump administration is behaving erratically and irresponsibly. For the good of the country, the president needs to start focusing on the budget."