The mayors of Paris, Madrid, Athens and Mexico City have said they have committed to ridding their cities of diesel engines by 2025 to improve air quality.
The announcement comes as a large group of mayors of major cities meets in Mexico to discuss climate change.
Paris Mayor Anne Hidalgo told the gathering the world's big cities will need $375bn of investment to curb climate change.
"It is a lot, but there is no other option. Together we will seek that money," Ms Hidalgo, the new president of the C40 network of big cities, said.
If that amount is made available "humanity will have a chance of surviving," she said.
The mayors were meeting to plot strategy in the face of climate change scepticism from US President-elect Donald Trump.
They said they planned to make commitments to reduce harmful emissions by promoting cycling in cities and renewable energy, among other measures.
As leaders of busy, polluted cities that are home to millions of people, the mayors gathered in Mexico City want countries to push on with adopting the so-called Paris Agreement to limit harmful emissions.
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Mr Trump has cast doubt on the accord, which aims to limit global warming to two degrees Celsius above pre-industrial levels.
The Republican billionaire has in the past vowed to tear up international climate agreements, though he said in an interview last week that he has an "open mind" about supporting them.
He had previously said global warming was a "hoax" invented by the Chinese and not scientifically proven.
Four major cities move to ban diesel vehicles by 2025: https://t.co/rbR0CJIMeT … via @BBCWorld #cities4climate pic.twitter.com/IgYFO9Wyjk
— C40 Cities (@c40cities) December 2, 2016
The C40 group's 85 cities include London, New York, Vancouver, Hong Kong and Seoul.
Los Angeles Mayor Eric Garcetti told the gathering that 38 US cities had sent a letter to Mr Trump to tell him they would push ahead with their efforts against climate change.
C40 executive director Mark Watts said in an analysis unveiled this morning that the world's big cities must collectively cut their carbon footprint by nearly half within a decade if the 196-nation Paris Agreement is to be met.
With only one degree Celsius of warming so far, the world has already seen an upsurge in extreme weather, including droughts, superstorms, heat waves and coastal flooding boosted by rising seas.
Dublin could become diesel free
The Director General of Society of the Irish Motor Industry has said it is possible for Dublin to become a diesel free city within the next ten years but that proper planning needs to be part of the process.
Speaking on RTÉ's News At One, Alan Nolan said a move to electric cars is part of the solution, adding that a move away from diesel as a fuel would not kill off the motor industry.
Mr Nolan said there needs to be a number of solutions, instead of relying solely on electric vehicles.
He said education also needs to form part of the process as for a large part of the population diesel is the "workhorse fuel".
Meanwhile, the Director of Green Budget Europe, an organisation that works to shift taxes on to pollutants across the EU, has said there needs to be more investment in public transport to allow for a move away from the use of diesel.
Also speaking on News at One, James Nix said there are a number of measures that the Government can undertake to reduce the use of diesel such as looking at Vehicle Registration Tax and the fuel tax reduction for diesel.
He said 70% of car sales in Ireland are for diesel cars and that needed to be pulled back.
Mr Nix said the measures must be taken now so Ireland is not dealing with health problems down the line.
