ADELAIDE, Australia – Alexander Downer announced Thursday he is quitting Australian politics following a career as the country's longest-serving foreign minister and one of its highest-profile leaders of the past decade.

Downer, who was ousted from power at elections last year along with the rest of Prime Minister John Howard's conservative government, said he is in talks on taking a job as a special U.N. envoy on the conflict in Cyprus.

Downer, 56, declined to run for the leadership of his Liberal party after the coalition that had ruled since 1996 lost elections last November and has languished on the back benches of parliament while considering his future.

Confirming long-rumored plans, Downer told reporters he would join a political and business consultancy in his home town of Adelaide and take up a part-time university teaching post.

His resignation from parliament would become effective on Monday, Downer said.

“I don't really have regrets,” Downer told reporters. “I just feel that I did my best, I worked incredibly hard and I argued for the things I believed in.”

Downer stamped his mark on the world stage during a period of expanding Australian influence, from growing economic clout in Asia to sending troops to Iraq and Afghanistan as well as East Timor and the Solomon Islands.

Appointed immediately after Howard's election, Downer was the former prime minister's closest foreign policy adviser for the full length of the government.

Prime Minister Kevin Rudd said he discussed Downer's possible Cyprus appointment during a conversation with U.N. Secretary General Ban Ki-moon late Monday.

The Australian newspaper reported in May that Ban was keen to use Downer to resuscitate stalled diplomatic efforts to reunify the island, which has been divided since 1974 when Turkey invaded after a failed coup aimed to unite the island with Greece.