The political leaders of the US, Canada and Mexico have announced a landmark agreement on climate change that could see further development of hydropower in the countries.

Barack Obama, Justin Trudeau and Enrique Peña Nieto unveiled a North American deal that commits their countries to generating 50 per cent of electricity from "clean" sources, including hydro, by 2025.

It also commits them to phasing out fossil fuel subsidies by 2025, decrease methane emissions, and invest in clean energy projects.

"The agreement that we’ve concluded today values our shift towards clear renewable energy," Trudeau said at a joint press conference at the National Art Gallery in Ottawa, Canada, at the conclusion of a one-day summit between the leaders.

A statement from the White House said that clean energy deployment would include renewables, nuclear energy and carbon capture and storage. There will also be joint efforts to improve energy efficiency by aligning ten appliance efficiency standards, and investment in cross-border transmission lines, it said.

The three leaders have also committed to joining the Paris climate agreement in 2016, in addition to reaching successful conclusions in other key international negotations this coming autumn. This includes amending the Montreal Protocol to reduce HFC emissions and limiting emissions from the aircraft sector through the International Civil Aviation Organisation.