Ronaldson says he will formally tender his resignation when the party has preselected his replacement.
“My decision will allow the party to continue the renewal process and will allow me to pursue opportunities elsewhere,” he said in a statement on Friday.
Ronaldson spent more than 17 years on the frontbench, serving as minister for veterans affairs and special minister of state in the Abbott government.
He was relegated to the backbench when Malcolm Turnbull took the top job, with his portfolios handed to Stuart Robert and the now-embattled Mal Brough.
“I will always remain extremely grateful to Tony Abbott for giving me this opportunity,” Ronaldson said.
He insists he maintains a “close friendship” with Turnbull and his wife Lucy.
“Outside of our shared political experiences, Cate and I, and the Turnbulls share the joys of grandparenthood.
“I have no doubt Malcolm’s time as PM will be that of a nation builder and a driver of national prosperity.”
Ronaldson said his decision wasn’t easy.
He served as a federal MP for Ballarat for almost 12 years and served as a Victorian senator for over a decade.
“Like all political families, mine has paid a high price allowing me to pursue my passion and goals.”
Frontbencher Simon Birmingham paid tribute to his “good friend & Canberra housemate” on Twitter.
“Top bloke, passionate community leader & powerful contributor,” he said.
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