The Liberals are promising a suite of family-friendly benefits, including a boost to the Canada Child Benefit (CCB) for babies and a 15-week leave program for adoptive parents.

Liberal Leader Justin Trudeau used a Tuesday morning campaign appearance in St. John's to announce the proposed measures, which include making parental benefits tax-free.

Calling it a "big step forward," Trudeau pledged that a re-elected Liberal government would give families up to $1,000 more by increasing the CCB by 15 per cent for children under the age of one. The CCB was introduced in 2016 and the Liberals have credited it with lifting 300,000 children out of poverty.

"No one should have to choose between their paycheque and their family, a choice that moms are still confronted with more than dads," Trudeau said. "People should be focused on spending time with their baby, not worried about how they'll pay their bills."

Liberal leader Justin Trudeau promises more money for families with children under the age of one. 0:55

The Liberal proposal to make maternity and parental benefits tax-exempt at source means no federal taxes would be taken off the Employment Insurance payment, Trudeau said. It goes one step further than the Conservative Party proposal to bring in a non-refundable tax credit for maternity or parental benefits.

"You'll get every dollar right when you need it, since no taxes will be taken off the EI cheque when new parents receive it," Trudeau said.

The proposed new 15-week leave for adoptive parents would give them the same benefits as those who have a baby through natural birth. That would mean an extra $7,000 in help for the average family claiming the new adoptive leave, according to the Liberal Party documents.

Trudeau said these measures lay the groundwork to "go even further."

A re-elected Liberal government also would work with the provinces and territories to establish Guaranteed Paid Family Leave for parents who don't qualify for paid leave through EI during the first year of their child's life. The party's proposal calls for the program to launch in 2021.

'Ambitious program'

"This will be an ambitious program to make sure that no one gets left behind," Trudeau said.

Lindsay Tedds, an economics professor at the University of Calgary, said she's awaiting finer details on how the tax measures would be implemented in order to fully assess both proposals. She said one advantage of the Liberal plan over the Conservative one is that claimants won't have to worry about the tax liability.

"A lot of women who work earn a lot of income before they go on maternity benefits, and they actually pay a higher tax rate on that income than 15 per cent," she said. "So the Conservatives haven't accounted for that, whereas the Liberals are accounting for that ... The Liberals can actually tout this as tax-free maternity and parental benefits. The Conservatives can't."

According to Liberal Party calculations, the proposed measures would cost about $800 million in 2020-21, rising to $1.2 billion in 2023-24. Costing analysis from the parliamentary budget officer (PBO) has not yet been released.

Asked why none of the Liberal campaign commitments so far have come with PBO costing, Trudeau said the PBO has been "very much engaged" with the Liberal Party on its platform.

"We will have a full costing of the Liberal platform with all the great work done by the PBO in due course. That is something people expect and people want to have," he said.