The French President Francois Hollande is in the United States for the first state visit by a French leader in 18 years.

He and US President Barack Obama have used the occasion to celebrate what they call an “enduring alliance” and publish a joint letter calling for a global pact to fight climate change.

They say a clean energy partnership will create jobs as well as support developing countries shift to low-carbon energy.

The pair will also hold talks on Iran, Syria and a US-EU trade deal.