One of federal parliament’s newest senators has resigned less than one month after being sworn in.

NSW One Nation Senator Warwick Stacey on Tuesday resigned from the senate due to health reasons.

“I don’t think a person elected to parliament should be anything less than completely dedicated to a role entrusted to them by voters, so I’m resigning to make way for someone who can do that on behalf of the people of NSW,” he said.

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“Unfortunately, I will be unable to fully dedicate myself to the role as I deal with my personal health issues.”

Stacey, a former hostage negotiator and SAS soldier, was sworn into federal parliament in July after winning the sixth and final senate slot for NSW at the May election.

He only sat in parliament for the first two sitting weeks of the term as one of four One Nation senators in the upper house.

One Nation will announce Stacey’s replacement in coming weeks.

Party leader Pauline Hanson thanked Stacey for his efforts during the election campaign.

“Warwick Stacey is a man of principle and a great Australian,” she said.

“It is with profound regret that we farewell him from the senate so soon after he was elected.

“I wish Stacey all the very best with his health and his future.”