*This story has been updated to correctly note that the campaign spending limit is $1.3-million, not $1.3-billion. iPolitics apologizes for the error.

The Liberal Party is launching partisan campaign ads aimed at the federal Conservatives with three months to go before a $1.3-million limit on pre-writ advertising.

CBC on Monday aired a snip of the first round — radio ads accusing the Conservatives of planning to return to a time before climate change skepticism started to recede as severe weather events became more frequent around the world. Canadian Press reported the official ad blitz begins on Tuesday.

“I’m Justin Trudeau,” the ad opens. “Climate change is a real and serious problem, we have a plan to fight it.

“Some politicians want to go back to the Harper years, when pollution was free,” Trudeau says in the ad, which ends with a Liberal Party of Canada legal authorization at the tail end.

All registered federal political parties will be limited on the amount they may legally spend on partisan advertising in the designated pre-writ period, beginning June 30, before the chief electoral officer issues writs of election for the general election set for Oct. 21.

In a sweeping overhaul of the Canada Elections Act that passed through Parliament and received Royal Assent in a rush of last-minute Senate work last December, the government struck an agreement to raise the pre-writ advertising to $1,300,000. Third parties who want to place partisan ads in the election are limited at $700,000.

The Conservative Party mounted a $2-million ad campaign in 2018. If the Trudeau government sets the election period at the minimum of 37 days, the timing would leave two-and-a-half months for spending by each party that would not be included in limits still to be set for the writ period. If Trudeau and his party decide to go with a maximum of 50 days for an election writ period — a limit set by Parliament under the new election law provisions — there would be a two-month opening for pre-election spending.

The Liberals brought in the pre-writ spending limits after the Conservative Party, consistently ahead of the other parties in fundraising, had led all parties in costly ad campaigns before previous election period limits kicked in.

In the wake of Liberal turmoil over allegations Trudeau and key aides pressured former attorney general Jody Wilson-Raybould in a corruption prosecution against Montreal’s SNC-Lavalin, Trudeau this week launched an attempt to mitigate damage as Parliament takes three weeks off for annual March breaks.

Trudeau, along with Agriculture Minister Lawrence MacAulay and Defence Minister Harjit Sajjan, began the week with a $37-million funding announcement in Charlottetown, with an early morning breakfast fundraiser before the funding event. Trudeau, MacAulay and Sajjan were all scheduled to appear at the party fundraiser, Liberal Party details show.

The day was scheduled to end with a Liberal climate change rally in Toronto.

The week also began with more bad news for Trudeau and his party as a newly released Nanos Research poll showed a dive in Liberal fortunes over the SNC-Lavalin affair.

A poll of 1,000 Canadians showed a dramatic drop in public confidence for the government after explosive testimony from Wilson-Raybould over pressure she faced from the government to interfere in a bribery prosecution against the Montreal company by the federal director of public prosecutions.

Before Jody Wilson-Raybould’s testimony on Wednesday alleging the pressure, a Nanos survey had found 17 per cent of Canadians said the affair will be a factor when they vote in the 2019 election.

The number of concerned respondents jumped by nearly 10 per cent, to 26 per cent after the testimony, a second Nanos survey of the same 1,000 Canadians found after the committee hearing.

Before Raybould-Wilson testified, 17 per cent of respondents said they considered Trudeau the most ethical federal leader. Trudeau ranked third behind Green Party Leader Elizabeth May, who was rated as the most ethical by 23 per cent of the respondents. Conservative Party Leader Andrew Scheer had 21 per cent saying he was the most ethical.

But in the second poll, last Friday, Trudeau dropped to 12 per cent support, just ahead of NDP Leader Jagmeet Singh, who will take a seat in the Commons for the first time after winning a byelection in the B.C. riding. May climbed to 29 per cent who thought she was the most ethical, and Scheer stayed put at 21 per cent.

Perhaps more devastating for the Liberals, the second survey found a dramatic increase in belief that the Green Party is the most ethical federal party, with 29 per cent of the respondents rating the Greens at the top when it comes to ethics.

The Conservative Party placed second, at 21 per cent, followed by the NDP at 7 per cent and only 12 per cent of respondents saying they thought the Liberal Party was the most ethical.

Support for the Liberal Party was highest in Quebec.