Two Conservative members of the Senedd have quit its COVID committee over a row about taking the oath.
The Wales COVID-19 inquiry special purpose committee was set up by politicians in Cardiff Bay to fill any "gaps" in the UK-wide inquiry's scrutiny of decisions made by the Welsh government.
Tom Giffard said he had resigned as co-chair of the committee after Welsh Labour members voted against an amendment which would have allowed witnesses, including ministers, to give evidence under oath.
Fellow Conservative Senedd member Sam Rowlands has also stepped down from the committee.
In a statement, Mr Giffard said that he had resigned "with a heavy heart" and that the Welsh Conservatives would "no longer engage with the committee".
"Families who lost loved ones deserve honest answers, yet Labour's decision to block oaths being taken undermines any chance of getting to the truth," he said.
"Without the safeguard of requiring witnesses to speak under oath, this committee has become a pointless talking shop."
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