After the unprecedented Sandringham summit on Monday, the Queen gave her backing to Harry and Meghan's new "independent life" away from full-time royal duties and said they will begin a transition period living in the UK and Canada, The Daily Mail reported on Tuesday.
The move has raised questions over the costs of the couple's security during their time in North America and who would foot the bill.
Addressing the media, Trudeau said on Monday: "That is part of the reflection that needs to be had and there are discussions going on.
"We're not entirely sure what the final decisions will be, what the dispositions are and those are decisions for them.
"I think most Canad are very supportive of having the royals here, but how that looks and what kind of costs are involved, there are still lots of discussions to have."
Trudeau further said that the federal Canadian government had not been involved "up until this poin" about what the couple's move to the country will involve.
"There are still a lot of decisions to be taken by the royal family, by the Sussexes themselves, as to what level of engagement they choose to have.
"We are obviously supportive of their reflections but have responsibilities in that as well,' he said, adding that the Sussexes enjoyed a "general feeling of appreciation" in Canada.
Meanwhile, the Buckingham Palace, UK Cabinet Secretary Mark Sedwill and the Home Office have already discussed the future of the couple's security.
Asked about the issue of who will fund their security, the British Home Secretary Priti Patel told the BBC: "I'm not going to provide any detailed information on the security arrangements for either them or any members of the Royal Family or for any protected individuals - that's thoroughly inappropriate for me to do so."
Following the emergency meeting on Monday, the Queen said that she'd held "very constructive" talks with Harry, his brother Prince William and their father Prince Charles in a bid to chart a course through the fallout of the Sussexes' January 8 announcement.
"My family and I are entirely supportive of Harry and Meghan's desire to create a new life as a young family," the 93-year-old monarch said.
( With inputs from IANS )