(CNN) All ten Democrats on the Senate committee tasked with considering President Donald Trump's pick to lead the Environmental Protection Agency boycotted the meeting to vote on Oklahoma Attorney General Scott Pruitt.

The Democratic protest delayed the vote, leaving the Environmental Protection Agency -- an organization that has been a hotbed for controversy during the Trump transition - without a head.

"Not having a vote on this nominee today, not organizing this important committee, is a shame," Republican Sen. John Barrasso, chairman of the committee, said before adjourning the committee.

Democrats, outside the hearing chamber, complained about Pruitt not providing answers regarding his record as Oklahoma attorney general, while Republicans inside the chamber vented about the boycott.

"If Scott Pruitt is serious about serving as our next EPA Administrator, he should be more than willing to provide @EPWDems complete answers," Democratic Sen. Tom Carper of Delaware tweeted shortly after the boycott was announced.

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