John Manley, shown in a file photo, held several cabinet positions, including Finance and Foreign Affairs. (CBC)

Former deputy prime minister John Manley says he may return to the political scene and join the race to succeed Liberal Leader Stéphane Dion.

Speaking in Ottawa on Monday, Manley said many people across the country have urged him to toss his hat into the ring, but he's not sure he's ready to take the leap.

Manley served as minister of a number of departments during his 16 years as a member of Parliament, including Finance, Foreign Affairs and Industry, but has worked off Parliament Hill for the past few years.

Last year, Prime Minister Stephen Harper named Manley to chair a high-profile independent review panel on Canada's role in Afghanistan.

His report became the basis of the Conservative government's demand that NATO supply extra troops and equipment as a condition of Canada's continued involvement in Afghanistan past 2009.

A personal and political choice

"I am assessing it from both a political and a personal perspective," said Manley. "I like my life at the moment. I like what I've been able to do still in public policy, despite leaving public office, and those are major factors for me."

Manley, 58, currently practises law in Toronto and Ottawa and sits on several corporate boards.

The former cabinet minister said he's aware of the price paid for entry into public life, having run in the 2003 leadership campaign.

Months after entering the race, he dropped out, citing insufficient support against front-runner Paul Martin, who went on to become leader and prime minister.

"I've been through it one time, although it wasn't widely reported at the time," said Manley.

"I know how hard it is, so … I'm not jumping off the diving board until I'm pretty sure there's some water in the pool."

In 2003, Manley turned down an offer to become Canada's ambassador to the U.S. after announcing his departure from federal politics.

Manley chose not to run in the 2006 Liberal leadership race, citing personal reasons.

Michael Ignatieff and Bob Rae, both front-runners in the previous leadership race, are expected to take another run at the top job.

Others rumoured as possible leadership contenders include former New Brunswick premier Frank McKenna, former leadership rivals Martha Hall Findlay and Gerard Kennedy, and MPs Denis Coderre and Dominic LeBlanc.

Dion is remaining at the helm of the party until his successor is selected at a leadership convention. No date has been set, but the convention could take place next May in Vancouver.