The former US vice president said there is a 'better than even' chance that the US will stick with the Paris Agreement
The former US vice president Al Gore has said the Trump presidency so far has proven that "no one person" can stop efforts to slow climate change.
A number of actions by the Trump administration have caused major concern among climate activists - such as the decision to appoint a climate change sceptic to lead the US Environmental Protection Agency (EPA).
President Trump has also threatened to pull out of the historic Paris climate change agreement.
Speaking at the Cannes Film Festival during a panel about his new documentary An Inconvenient Sequel, Mr Gore suggested there is a "better than even chance" that President Trump will keep the US as a party to the Paris Agreement.
"I don't know that he will, but I think there is a chance that he will," he observed.
Gore also insisted that the momentum behind stopping climate change is continuing.
"We now know after four months of the Trump administration that no one person, not even a president, can stop the climate movement," he told reporters. "We have seen large states like California, New York and many others now making faster progress than the commitments made by former president Obama during the Paris Agreement.
"We've seen businesses now make commitments to adopt 100% renewable energy - and more are doing so every day."
He added: "In a growing number of areas around the world, it is now cheaper to get electricity from the sun, and the wind, and to store it in batteries, and to use it for electrical vehicles, than it is to continue using the dirty polluting fuels of the past."
An Inconvenient Sequel: Truth to Power - a follow-up to the Oscar-winning An Inconvenient Truth - is due to be released in August, although has received mixed reviews from critics.