Britain will ban the sale of new petrol and diesel cars from 2035, five years earlier than previously planned, Prime Minister Boris Johnson will announce on Tuesday as he launches a major U.N. climate summit due to take place in Glasgow in November.

Johnson will launch COP26, a two-week conference seen as a moment of truth for the 2015 Paris Agreement to combat global warming, at an event alongside Italian Prime Minister Giuseppe Conte and broadcaster and naturalist David Attenborough.

"Hosting COP26 is an important opportunity for the UK and nations across the globe to step up in the fight against climate change," Johnson said in a statement released by his office ahead of a speech in London on Tuesday.

"As we set out our plans to hit our ambitious 2050 net zero target across this year, so we shall urge others to join us in pledging net zero emissions."

Johnson will call for international efforts to reach net zero as early as possible, including through investment in cleaner technology, preservation of natural habitats and measures to improve resilience to the impact of climate change.

The government said that, subject to consultation, it planned to bring forward an end to the sale of new petrol and diesel cars and vans to 2035, or earlier if a faster transition was possible. It also said it would include hybrids.

Cities and countries around the world have announced plans to crack down on diesel vehicles in the wake of the 2015 Volkswagen emissions scandal and the EU is introducing tougher carbon dioxide rules.

France plans to ban the sale of fossil fuel-powered cars by 2040 whilst Norway's parliament has set a non-binding goal that by 2025 all cars should be zero emissions.

But diesel and petrol models still account for 90 percent of sales in Britain, and some prospective buyers of greener models are worried about the limited availability of charging points, the range of certain models and the cost.