ST. JOHN'S - Canadian Industry Minister Brian Tobin, long considered a favorite to one day replace veteran Prime Minister Jean Chretien, dropped a political bombshell on Monday by quitting federal politics for family reasons.

Chretien moved quickly to fill the void, announcing within minutes that he would shuffle his cabinet at 9.30 a.m. EST (1430 GMT) on Tuesday.

Chretien has been tipped to make changes to his cabinet for some time, but leading government figures such as Finance Minister Paul Martin and Foreign Minister John Manley are expected to keep their jobs.

Tobin, citing the "heavy demands on family time" made by political life, said he had already resigned as minister and would give up his parliamentary seat in the days ahead.

The driven 47-year-old former journalist had until now been the leading left-leaning candidate to eventually replace Chretien, and his stunning departure threw open the maneuvering to succeed the 68-year-old prime minister.

Tobin -- one of the most colorful politicians in Canada and a close Chretien ally -- told a news conference in his native Newfoundland that after 24 consecutive years in politics he could no longer summon the energy and commitment to carry on.

"Once that fire is not there in the morning to get up and do it again, I believe it's time to move on.`???is is what has happened in my case," he said.

"This decision is not strategic, this decision is not political, it is personal. It represent a new chapter -- I hope -- in my life and that of my family."

His wife Jodean took part in the news conference and his three children, the youngest of whom is 15, were in the room.

Tobin admitted he had no idea what he would do next and questions remained about his surprise decision. CBC radio in Newfoundland reported that, as late as last week, he had held a meeting in Halifax with a group of donors who had each promised to contribute C$25,000 ($15,600) to his leadership campaign.

Tobin was the chief rival of fiscally more conservative Finance Minister Martin, 63, in a race to head the Liberal Party when Chretien eventually decides to go.

His departure from the field leaves Health Minister Allan Rock as the leading contender on the Liberal left. The other main candidate is Foreign Minister Manley, who, like Martin, is toward the right-wing of the party.

Tobin, who revealed he had told Chretien more than a year ago he was inclined to quit politics, went to the prime minister's residence on Sunday to inform him of his decision, in a meeting that lasted several hours.

The stocky, quick-witted Tobin, a big hit with Chretien as well as rank-and-file Liberals, was elected to Parliament in 1980 and first rose to prominence as a member of the so-called "Rat Pack", a group of opposition legislators who did all they could to make life hard for then then ruling Conservatives.

When the Liberals won the 1993 election Tobin became fisheries minister and made more headlines in 1995 when he ordered the seizure of a Spanish trawler in international waters during a dispute over turbot fishing.

That incident earned him the nickname "Captain Canada" and he gained further stature in October 1995 by helping to organize a massive unity rally in Montreal just days before the French-speaking province of Quebec voted narrowly not to split away from Canada.

Tobin quit federal politics in 1996 to make a successful run for the premiership of Newfoundland. He returned to Ottawa in October 2000 when Chretien made him industry minister. In a federal election held the next month he helped ensure a Liberal victory in Newfoundland and the other Atlantic provinces.

Tobin has made no secret of his political ambitions. He had been working on his French, considered a prerequisite for any prime minister in bilingual Canada, and had shown no signs of being fed up with politics.

As industry minister he pushed for spending billions of dollars on an "innovation agenda," most notably advancing the idea of extending high-speed Internet to all of Canada.

But in last month's federal budget Martin trimmed Tobin's ambitions, making it clear that, in the current economic downturn and in the wake of the Sept. 11 attacks on the United States, Ottawa could not afford to finance such a scheme in the near term.

(With additional reporting by David Ljunggren and Irene Marushko in Ottawa and Randall Palmer in Toronto)

($1=$1.59 Canadian) Nampa-Reuters