Three national political leaders smiled and cheered as they marched together in Vancouver's Pride parade on Sunday, while denouncing the latest wave of gun violence to occur in the United States.

Prime Minister Justin Trudeau, federal NDP leader Jagmeet Singh and federal Green Party leader Elizabeth May all said they were glad to be together in Vancouver, celebrating inclusiveness and tolerance at one of the most anticipated annual events in the city.

Trudeau said politics are becoming polarized around the world and events like Pride in Vancouver are an opportunity for political leaders to agree to stand up for human rights and communities that are marginalized.

"That's particularly why I'm glad to be here walking alongside a number of party leaders including Jagmeet Singh and Elizabeth May," he said. "This is important, it shows that we are in favour of human rights, in favour of defence of Canadians."

Jagmeet Singh leads the NPD crowd on a bicycle. (Maggie MacPherson/CBC)

Trudeau and the two other leaders at the parade said they were shocked and saddened by two back-to-back shooting deaths in the U.S. on Saturday.

Singh said it was important to describe the violence as domestic terrorism and hate.

"We've got to call it out," he said.

May said the violence in the U.S. was a complete contrast to the joy, celebration and togetherness taking place on Vancouver's streets on Sunday.

"This is Canada, the prime minister, Liberal, Jagmeet Singh, NDP, me Green," she said.

"And we are about to go into a campaign to win seats to form government against each other but we are together because this matters. This is inclusive and supportive."

Jody Wilson-Raybould, Independent MP for Vancouver Granville, poses with a member of Vancouver Fire Fighters Local 18. (Maggie MacPherson/CBC)

The theme for this year's Pride in Vancouver was "still fighting 50 years later," marking the partial decriminalization of homosexuality in Canada and the Stonewall uprising of 1969 in New York City, which gave birth to the Pride movement that spread across the globe.

Yet organizers said members of the LGBT community such as trans people, non-binary individuals and people with disabilities are still being left out and left behind and more needs to be done.

Justin Trudeau waves a Canadian Pride Flag at the corner of Robson and Denman street. (Maggie MacPherson/CBC)

This year, Vancouver Pride banned the Vancouver Public Library from participating in the parade because it allowed a controversial speaker, Meghan Murphy, to book a space at the library in January.

The same thing happened to UBC over allowing another speaker, Jenn Smith, at a campus event in June.

Both Murphy and Smith face criticism over their views about transgender rights policies and legislation.

Trudeau says he supports the Pride society's right to invite and include organization it believes are allies.

"I know that the goal of including everyone is really important but it's also really important to take a strong stance against intolerance and that's one of the reasons why I'm so glad to be here today, to send that message to people right around the country that it's not OK to discriminate against marginalized people," he said.

Trudeau also said he was disappointed that Conservative Party leader Andrew Scheer did not participate in the Vancouver Pride parade.