London mayor Boris Johnson is travelling to Paris for talks with other leaders on tackling climate change, as a crucial UN summit on global warming continues.
The mayor will attend meetings with leaders from other cities which are part of the "C40" group of major world cities, including New York and Seoul, South Korea, that are taking the lead on action to tackle climate change.
He will also visit a thermal power station which uses water from the river Seine to cool five million square metres of public buildings, cutting their need for air conditioning and saving on carbon emissions.
A similar scheme is planned for London, using the Thames to heat homes in Greenwich.
Mr Johnson is also expected to pay his respects to the victims of the recent Paris terror attacks during his visit to the French capital.
His visit comes as negotiators from 195 countries at the UN climate summit attempt to hammer out a new comprehensive deal to curb greenhouse gas emissions and prevent "dangerous" climate change.
Ahead of the mayor's trip to Paris, the London Assembly agreed a motion urging Mr Johnson to make the "climate emergency" a top priority for his remaining time in office.
The Assembly also called on the mayor to urge fellow city leaders to take the strongest measures possible to reduce greenhouse gas emissions, and for him to protect climate change programmes in next year's budget.