Justin Trudeau made a stop at Buckingham Palace on Wednesday where he met Queen Elizabeth for the first time as Canada's prime minister.

"Very nice to see you again," the Queen told Trudeau as they shook hands. "In rather different circumstances, isn't it?" she said.

Trudeau was a child in 1977, when he first met the now 89-year-old monarch alongside his father, former prime minister Pierre Trudeau.

"I will say, you were much taller than me the last time we met," Trudeau commented, as cameras recorded the initial moments of their meeting.

The Queen remarked that Trudeau must be in the midst of a "busy time."

"Just a little bit," Trudeau said. "But it's a good one. There's a tremendous positive energy."

Following the meeting, Trudeau delivered a speech at Canada House where he said the Queen has played an important role in Canada's history.

"She was of course gracious and insightful, with a unique and valuable perspective," Trudeau said. "Her Majesty has been an important part of Canada's history and I am confident will remain an important part of our continued progress and our future."

In comments released by his office prior to Wednesday’s audience, Trudeau said he knew how much his father liked Queen Elizabeth.

"You could tell my dad was really proud to be introducing his son to the Queen," he said.

Trudeau's London trip also includes a sit-down with Prime Minister David Cameron. He will leave Britain on Thursday for Valetta, Malta, where the 54-country Commonwealth grouping is holding its biennial leaders' summit.