LOWER SACKVILLE, N.S. — If Nova Scotia's New Democrats win the June 13 election, they would preside over the "death of the economy," Premier Rodney MacDonald warned Monday, turning his back on three years of close co-operation between the minority Conservatives and Opposition NDP.

On the first full day of campaigning, the 34-year-old premier veered off his feel-good message track and suggested his main opponents scared voters. "Two things are certain, death and taxes," MacDonald said during a campaign stop in Lower Sackville, a Halifax suburb. "The other two things that are certain are that the Liberals would raise your taxes and the NDP would be the death of the economy."

Opposition critics and political observers said they were stunned by MacDonald's harsh comments, given that the Tories under former premier John Hamm had relied on the NDP's low-key support through three budgets to remain in power.

The minority government also adopted several policies championed by the NDP, including: ending the practice of making seniors in nursing homes pay for their health care; raising the minimum wage and overtime pay; and placing a moratorium on school closures.

In last week's budget, MacDonald went further, promising to rebate the provincial sales tax on home heating fuels -- a key plank of the NDP policy platform for the past seven years.

NDP Leader Darrell Dexter, a 48-year-old former labour lawyer, predicted MacDonald will reconsider his comments.

"I'm sure the Conservatives who have worked with us on three successive budgets wouldn't have done that if they thought it would be the death of the economy," he said.

Dexter also pointed out that New Democrats insisted on balanced budgets while the minority government was in power.

With the Tories holding only 25 of the 52 seats in the legislature, the ruling party had relied on the 15 NDP members for their political survival. The 10 Liberals have opposed the government at most every turn.

On Monday, the premier wouldn't back away from his incendiary comments, saying the NDP is trying to take too much credit for his government's progress.

"The reality is that if we didn't make the tough choices back in the early years of government, we simply wouldn't be able to make the investments we are making today," said MacDonald, who replaced Hamm only three months ago.

"I've heard very little about lowering taxes from the NDP on the corporate side, on the personal income tax side."

David Johnson, a political scientist at Cape Breton University, said the premier's decision to bash the NDP so early in the campaign suggests MacDonald sees the party as his main opponent.

But the hard-line approach could backfire.

"I think it's cheap politics," Johnson said.

Liberal Leader Francis MacKenzie, campaigning in Bedford, N.S., where he hopes to win a seat, described MacDonald's warnings as "alarmist."

"I think he had too much sun on the weekend...because if anyone has raised taxes, it's been the Conservative government."

MacKenzie noted the Conservatives presided over the historic buildup of the province's $12.3-billion debt in the 1980s.

Earlier in the day, MacDonald appeared to stumble when asked whether he remains committed to passing all the measures in the budget if his party is elected to govern.

MacDonald would only say he is committed to passing a fiscal document that is "very similar" to the one tabled May 9.

Later, MacDonald muddied the waters by suggesting the budget would be "exactly the same," except for a "an additional few hundred thousand here or there."

When asked if that meant more spending would be introduced during the 31-day campaign, he said: "Not in this fiscal year."

MacDonald said any new spending commitments made during the campaign will be included in budgets beyond 2006-07.