Senate President Scott Ryan is bringing forward his retirement and won't return to federal parliament when it resumes next month.
The Victorian Liberal senator previously signalled he would retire at the next election but on Friday brought that plan forward.
The move creates a casual vacancy for his seat and means senators will have to elect a new president.
Senator Ryan, who was first elected to federal parliament in 2007, labelled his service to parliament a privilege.
"I would like to especially acknowledge the efforts and understanding of all senators and staff, working with the challenges posed by various restrictions that has ensured that the Senate and its committees could continue to undertake our work throughout the COVID-19 pandemic," he said.
He also paid tribute to House of Representatives Speaker Tony Smith, who will retire at the next election due by May next year.
