Prince William on Wednesday hailed his late grandmother's passion for the environment as he called for the "fastest change the world has ever known" in transitioning to sustainable energy sources.

The prince, now heir to the throne after Queen Elizabeth II's death, sent a pre-recorded video message to an innovation summit in New York for the annual Earthshot Prize, which he created in 2019 to reward efforts to combat climate change.

"Although it is the saddest of circumstances that means I cannot join you in person today, I am pleased to be able to join you in video," he said, two days after the funeral for his grandmother Queen Elizabeth II, who died on September 8.

"During this time of grief, I take great comfort in your continued enthusiasm, optimism and commitment to The Earthshot Prize and what we are trying to achieve," he added in the video, which was released by his Kensington Palace office.

"Protecting the environment was a cause close to my grandmother's heart, and I know she would have been delighted to hear about this event and the support you are all giving our Earthshot Finalists -– the next generation of environmental pioneers."

William, 40, who took on the title of Prince of Wales following his grandmother's death, presented the inaugural Earthshot prizes at a ceremony in London last October, with projects from Costa Rica, Italy, the Bahamas and India picking up prizes.

His environmentalism also follows the example of his late grandfather Prince Philip, a former president of the World Wildlife Fund, and his father, the new King Charles III, who has long warned of the dangers of climate change.

The prince acknowledged that the world "is an uncertain place right now", with conflict, soaring energy prices and food shortages hitting families around the world.

"While addressing these in the short-term, we must also remain resolutely focused on tackling the greatest challenges that threaten our tomorrow," he said.

"Together, we need to ensure the transition to sustainable solutions is the fastest and most endemic change the world has ever known."

England's Harry Kane and other European team captains will wear "OneLove" armbands during the World Cup in Qatar to fight discrimination, the Football Association announced on Wednesday.

Homosexuality is illegal in the Gulf state and organisers have battled to reassure rights groups that same-sex couples will not face action at the tournament, which starts on November 20.

Ten European nations, including England, France and Germany, have teamed up to support the season-long OneLove campaign to promote inclusion, which features an armband with a multi-coloured heart.

Kane and the captains of the seven other nations in the group who have qualified for the World Cup will wear the armbands in Qatar.

"I am honoured to join my fellow national team captains in supporting the important OneLove campaign," said Kane, who will wear the armband for the first time in Friday's Nations League match against Italy.

"As captains we may all be competing against each other on the pitch, but we stand together against all forms of discrimination.

"This is even more relevant at a time when division is common in society. Wearing the armband together on behalf of our teams will send a clear message when the world is watching."

Mark Bullingham, chief executive of England's Football Association, said the OneLove campaign, introduced in the Netherlands before Euro 2020, was a "visible show of support for inclusion in football".

He also said the FA was continuing to push for the principle of compensation for migrant workers and their families in relation to deaths and injuries suffered during construction projects.

Qatar has repeatedly faced criticism over conditions for migrant workers, but insists it has made major improvements in recent years.

Human rights groups this week urged more sponsors of the World Cup to support calls for compensation for workers and their families over alleged abuses.