Liberal Leader Justin Trudeau says the Conservative government's decision to delay its budget until at least April shows the prime minister is scrambling to come up with a plan amid plunging oil prices and economic uncertainty.

"They’re making it up as they go … I’m a teacher and their excuses are the political equivalent of 'the dog ate 
my homework,'" Trudeau told a crowd of supporters gathered for a rally in London, Ont., Tuesday night.

"Oil prices are through the floor, and Mr. Harper has no backup plan. None," he told a small room packed with hundreds of supporters.

Trudeau, who is in London for a two-day meeting with his caucus, was picking up on a theme he raised earlier in the day, saying a Liberal government under his watch would be more fiscally prudent than the ruling Conservatives.

"Mr. Harper is now facing a very different reality, which has him lurching about, searching for a plan B, making it up as he goes along," Trudeau said at a midday press conference.

Liberal Leader Justin Trudeau speaks to Liberal supporters in London, Ont.

Liberal Leader Justin Trudeau speaks to supporters at a Liberal Party rally in London, Ont. Tuesday. (Dave Chidley/Canadian Press)

Asked for details about his own party's economic platform, Trudeau told reporters the Liberals' full program would be released during an election campaign.

But Trudeau was adamant that a Liberal platform would include reversing the Conservative government's recently announced income-splitting plan.

"I think I've been very clear on … the prime minister's income-splitting plan, which gives over $2 billion of our rapidly now disappearing surplus to the richest 15 per cent of Canadians," he said.

"Canadians worked hard to get through some difficult years, and the fact is that our prime minister's priority is to support the wealthiest Canadians, like his family and mine, instead of actually building support for the middle class and those who hope to join," Trudeau said after his morning meeting with his caucus.

Earlier, in remarks to kick off his caucus meeting, Trudeau said he had visited Meridian Technologies Inc.​, an automotive parts supplier.

"The people of southwestern Ontario are amazingly resilient and have demonstrated that moving beyond manufacturing-based employment is something they're willing to do," Trudeau said 

"But as is the case for so many parts of the country, they need a partner in Ottawa."

Finance Minister Joe Oliver accused Trudeau of turning his back on the region's workers, saying in a written statement that "encouraging them to close shop is an insult to its entrepreneurs."

"Trudeau's high-tax, high-debt plan would devastate the industry just as it continues to recover from the global recession," Oliver said.

Trudeau would reverse income splitting

Conservative Susan Truppe, who is the MP for London-North-Centre, defended the government and accused Trudeau of being out of touch with hard-working Canadians.

Justin Trudeau, caucus

Justin Trudeau focused mainly on the Conservatives' handling of the economy and the budget in remarks to MPs and reporters on the first of two days of meetings. (Susana Mas/CBC)

"I don't think he really knows anything about what's going on in London and in southwestern Ontario," Truppe said in London on Tuesday.

Truppe said Trudeau's decision to reverse income splitting would "raise taxes" on families.

She also defended the government's decision to delay the budget, saying the government could not have foreseen plummeting oil prices. 

"I don't know what the surplus will be — obviously, the oil prices was sort of an unforeseen circumstance."

Deputy Liberal leader Ralph Goodale said delaying the budget sends the wrong message.

"It sends a message of real confusion on their part, a lack of confidence, a lack of direction. They've run out of gas and it doesn't seem that they know quite who is steering the bus."

Employment Minister Jason Kenney told CBC Radio's The House on Saturday that the government would have to further restrain spending in the next budget.

But The Canadian Press is reporting that a federal official is distancing the Conservative government from Kenney's remarks.

"Mr. Kenney was out making pronouncements over the weekend and government officials were very busy yesterday contradicting him," Goodale said before Tuesday's caucus meeting. "It really is entirely the wrong message to come from a government at a time of economic challenges."

While Trudeau made it clear the Liberals would reverse the Conservative's promise of income splitting, Goodale would not say whether a Liberal government would also scrap planned increases to the universal child care benefit.

Scott Brison said that promise was "less regressive" than income splitting.