President Donald Trump's pick to lead the Environmental Protection Agency advanced Thursday to the full Senate for a vote after Republicans rammed his nomination through committee in defiance of a Democratic boycott.

For a second straight day, Democrats refused to show up for committee nomination votes, and Republicans countered once again by temporarily suspending committee rules that require at least two members of the minority to be present for a vote to be held.

"We will not allow it to obstruct," Senate environment committee chairman John Barrasso said in a terse opening statement, delivered to a hearing room with no Democrats present.

Two minutes later, the committee approved Scott Pruitt 11 to 0 to be the next EPA administrator. His nomination heads to the Senate floor for a full vote.

Partisan tensions have climbed during Trump's first weeks in office, as the new president signs controversial executive orders aimed at rolling back health care reforms, approving two delayed pipelines, restricting new regulations and imposing travel bans on people from seven Muslim majority nations.

On Wednesday, furious Democrats boycotted a Senate Finance Committee vote on the nominations of Steven Mnuchin to head the US Treasury and Tom Price to run the Department of Health and Human Services.

They also refused to participate in that day's vote on Pruitt, whom they see as a fossil fuel industry ally and a global warming skeptic.

When they continued the boycott Thursday, Barrasso called the delay "unprecedented" and used the power of the majority to ram the nomination through.

"We had an election last November. The people spoke and now it is time to set up a functioning government," Barrasso said.

Senate minority leader Chuck Schumer hinted at the difficulties his Democrats had with Trump's cabinet picks. "Many of the nominees have philosphies that cut against the very nature of the department to which they were nominated," he said on the Senate floor.

The confirmation of another controversial pick, education secretary nominee Betsy DeVos, is in trouble, with two Republican senators announcing their opposition.

A confirmation vote on DeVos is expected Monday.