Canadians vote on Monday in what's expected to be one of the closest races in the nation's history.
On Wednesday, Trudeau, Conservative leader Andrew Scheer and NDP chief Jagmeet Singh were all stumping for votes in Quebec, a predominantly French-speaking province that is a key political battleground, home to 78 of the 338 seats up for grabs.
However, Elections Canada has since confirmed the tweet would not be considered foreign interference under the current elections laws, so long as it was not paid for or the person making it did not receive any form of payment.
Obama's endorsement came just hours after Trudeau, speaking to reporters in Montreal, accused the Conservatives of running "one of the dirtiest, nastiest campaigns based on disinformation that we've ever seen in this country".
As for Scheer's dire warning of a GST hike under a Liberal-NDP coalition, Singh flatly said the Conservative leader is lying. "It is unfortunate that the Conservatives keep having to make up attacks against us", Trudeau said in the Toronto suburb of Whitby.
The Conservative platform also includes several Harper-era policies that the Liberals turned away from, such as narrowly targeted tax credits for transit riders and for children's arts and fitness programs, and a promise to balance the budget in five years.
Much awaited launch of IPO got delayed by Saudi Aramco
There are indications that 2% of Saudi Aramco will be sold during the IPO, with as much as $40 billion raised. However, they have also expressed doubt over the company's valuation.
Most polls continue to suggest the Liberals and Conservatives are deadlocked in popular support, raising talk about potential minority or coalition governments.
Trudeau was scheduled to make four stops in Ontario before flying later on Saturday to the western provinces of Manitoba and Alberta, where anger against the Liberals is rising over government environmental measures that critics complain will hobble the energy industry. "Not whatsoever because it's not a progressive tax", Singh said in Port Alberni, B.C. Another 7.2 per cent chose the Bloc Québécois, 5.5 per cent backed the Greens, 3.3 per cent favoured Maxime Bernier's People's Party and 0.9 per cent said they'd vote for another party. The NDP has been dominant on the island but the Greens' two seats are there and they're looking for more.
"We have had a very open and transparent campaign, being held accountable to Canadians through the media", he said.
Trudeau pivoted Friday to Ontario after two days in Quebec, turning his attention to ridings outside Toronto.
Bernier barely lost the Conservative leadership to Scheer before quitting and starting his own party.