WATCH: Queen urges leaders to act quickly on climate at COP26

GLASGOW, Scotland — Queen Elizabeth II has welcomed world leaders to the U.N. climate summit in a pre-recorded video message, saying “the time for words has now moved to the time for action.”

Watch Biden’s remarks in the player above.

The 95-year-old monarch had been expected to attend the Glasgow summit, but she had to cancel the trip after doctors said she should rest and not travel. The queen recently underwent medical checks and spent the night at a London hospital — her first hospital stay in years.

In the video message, played Monday during a welcoming reception for presidents and prime ministers, the queen said she hoped that the conference will be “one of those rare occasions where everyone will have the chance to rise above the politics of the moment, and achieve true statesmanship.”

“History has shown that when nations come together in common cause, there is always room for hope,” she said in the video, which was recorded on Friday at Windsor Castle.

In a tribute to her late husband, Prince Philip, the queen said she was happy to welcome the delegates because the environment was a subject close to Philip’s heart. In a rare public display of emotion, she said she “could not be more proud” that Philip’s environmental work lives on through the work of their eldest son, Prince Charles, and his son Prince William.

The queen’s remarks follow a day of speeches by world leaders who turned up the heat and resorted to end-of-the-world rhetoric on Monday in an attempt to bring new urgency to the COP26 climate summit being held in Glasgow.

The metaphors were dramatic and mixed at the start of the talks. For British Prime Minister Boris Johnson, global warming was “a doomsday device” strapped to humanity. United Nations Secretary-General António Guterres told his colleagues that people are “digging our own graves.” And Barbados Prime Minister Mia Mottley, speaking for vulnerable island nations, added moral thunder, warning leaders not to “allow the path of greed and selfishness to sow the seeds of our common destruction.”

READ MORE: World leaders ramped up rhetoric ahead of international climate negotiations

After apocalyptic warnings from those three and a few others, a handful of more sedate — sometimes detailed — speeches followed. U.S. President Joe Biden and German Chancellor Angela Merkel avoided soaring rhetoric and delved into wonky policy.

“There’s no more time to sit back,” Biden said in a more measured warning that also apologized for his predecessor’s temporarily pulling the U.S. out of the historic 2015 Paris agreement, something he said put the country behind in its efforts. “Every day we delay, the cost of inaction increases.”

In addition to coaxing big carbon-polluting nations to promise more stringent emission cuts, French President Emmanuel Macron said European nations now have to shift from promises to action.

Earlier, Johnson — who is hosting the summit in the Scottish city of Glasgow — likened an ever-warming Earth’s position to that of fictional secret agent James Bond: strapped to a bomb that will destroy the planet and trying to defuse it.

He told leaders that the only difference now is that the “ticking doomsday device” is not fiction and “it’s one minute to midnight on that doomsday clock.” The threat now is climate change, triggered by the burning of coal, oil and natural gas, and he noted that it all started in Glasgow with James Watt’s steam engine powered by coal.

Johnson also pointed out that the more than 130 world leaders gathered for the leaders’ summit portion of the U.N. climate conference had an average age of over 60, while the generations most harmed by climate change aren’t yet born.

The conference aims to get governments to commit to curbing carbon emissions fast enough to keep global warming to 1.5 degrees Celsius (2.7 degrees Fahrenheit) above pre-industrial levels. The world has already warmed 1.1 degrees Celsius (2 degrees Fahrenheit). Current projections based on planned emissions cuts over the next decade are for it to hit 2.7C (4.9F) by the year 2100.

Increased warming over coming decades would melt much of the planet’s ice, raise global sea levels and greatly increase the likelihood and intensity of extreme weather, scientists say. With every tenth of a degree of warming, the dangers soar faster, they say.

The other goals for the meeting are for rich nations to give poor nations $100 billion a year in climate aid and to reach an agreement to spend half of the money to adapt to worsening climate impacts.

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