British MP's killing an 'act of terror': husband

The widowed husband of British lawmaker Jo Cox condemned her killing as an "act of terror" as he led worldwide commemorations Wednesday for a killing that sent shockwaves through Britain's EU referendum campaign.

"Jo's killing was political. It was an act of terror," Brendan Cox told around 5,000 people gathered in London's Trafalgar Square on what would have been her 42nd birthday -- as well as the eve of the vote.

Events were held around the world from Bangkok to Brussels, organisers said, while US President Barack Obama offered a tribute on Facebook to the lawmaker, who had volunteered on his first White House campaign.

"Jo knew that our politics, at its best, still works -- that, if we recognise our humanity in each other, we can advance the social justice, human dignity and peace that we seek in the world," Obama wrote.

Cox was shot and stabbed in the street last Thursday in her Batley and Spen constituency in Yorkshire, northern England, where another tribute was held Wednesday.

The global commemorations took place just hours before the polls open in a knife-edge referendum on whether Britain should stay in the EU or leave.

The killing of Cox, who wanted Britain to stay in the European Union and was a major advocate for refugee rights, forced a three-day suspension of the campaign.

"Jo lived for her beliefs. On Thursday she died for them. For the rest of our lives, we will fight for them in her name," Brendan Cox said.

"Thank you for the love that you have poured on our family since our world collapsed on Thursday," he said, his voice shaking with emotion.

"Amazing and deeply touching as all of this is, I wish I wasn't here.

"I'd rather be with Jo."

Cox said his wife would have spent her birthday trying to convince people to vote for Britain to stay in the EU.

A plane trailing a "Vote Leave" banner noisily flew overhead three times, including during Cox's speech.

The windower of murdered Labour MP Jo Cox, Brendan Cox (2R), sits with their two children Cuillin and Lejla on a boat during a floating tribute to Jo that was moored outside the Houses of Parliament in London, on 22 June 2016, the day that would have been Jo Cox's 42nd birthday. AFP PHOTO / LEON NEAL

- 'They can't win with bullets' -

Nobel Peace Prize winner Malala Yousafzai, who was shot in the head by Taliban extremists in her native Pakistan in 2012 for advocating education for girls, also spoke to the crowds in Trafalgar Square.

"I'm here today as a living proof that they can't win with bullets," the 18-year-old said.

Irish rockers U2, who worked with Cox on the Make Poverty History campaign, recorded a special tribute from Los Angeles.

"Jo Cox had all the patience in the world for people who needed help," said frontman Bono, before the song "Ordinary Love" was played.

A giant screen showed excerpts from her speeches in parliament and clips of her building a snowman with her children.

A small memorial for Cox was held Wednesday morning at Unicef headquarters in New York, while lawmakers in Paris also paid tribute by wearing white roses -- a symbol of hope and of her native Yorkshire.

The White Helmets, a Syrian civil defence volunteer group that Cox supported, also paid tribute, presenting Cox's husband with a white helmet.

Cox's killing was the first of a British lawmaker since 1990 when Ian Gow was assassinated by Irish Republican Army paramilitaries.

Thomas Mair, 52, has been charged with Cox's murder.

Among the crowd of well-wishers in London was the children's illustrator Karin Littlewood, from Batley, whose first boyfriend was the son of 78-year-old ex-miner Bernard Kenny who was stabbed while trying to protect Cox.

"My heart told me to come. I couldn't be anywhere else," she told AFP.

"It was very genuine. It just touched everybody's hearts."

Cox is survived by her five-year-old son Cuillin and three-year-old daughter Lejla.

A fund created in her memory has raised more than £1.3 million ($1.9 million, 1.7 million euros) from 40,000 donations for charities backing causes supported by Cox.