With the geopolitical situation at its most unstable since the cold war ended almost a quarter of a century ago, G7 leaders met recently in Hiroshima, Japan. No city in the world could better symbolise the catastrophic consequences of when global relations break down.

Maintaining relationships globally cannot just be the domain of nation states. In my own city of Bristol people speak 92 languages and hail from 180 countries of origin. When world leaders sit down next week to discuss nuclear disarmament and non-proliferation, Russia’s continued aggression in Ukraine, the growing threat of the climate emergency or the huge issue of food insecurity, they will be talking about issues that are central to the lives of our citizens.

It is why two years ago under the UK’s presidency of the G7, that we as Core Cities UK founded the Urban 7, a group of national city networks from across the G7 countries.

For the first time in Japan, our role was formally recognised in the main G7 proceedings. What is happening here is historic, it is a recognition by the presidents and prime ministers of some of the world’s biggest economies that local leadership is absolutely key to tackling global issues.

Nations may pledge but it is cities that deliver. Tackling the climate emergency could be the city’s biggest opportunity for this century.

As the world becomes increasingly urbanised – by 2050 more than two-thirds of the world’s population will live in a city - they are the places where the battle to meet Net Zero targets will be won or lost.

Cities have the density and scale to make the biggest impacts in decarbonisation. It will be our cities that need to lead the charge on ensuring a Just Transition where none of our citizens are left behind as we move towards a lower carbon economy.

We are focusing on the practical solutions. We have established the 3Ci initiative, in partnership with London Councils and the Connected Places Catapult, working together with urban investors to lever in the billions of pounds of private finance we need to clad our buildings, electrify our transport networks and generate sustainable energy.

We are sharing learning on these approaches across the Urban7, and will discuss with government ministers as part of the G7 process before taking our proposals to COP28 later this year in Dubai.

In my time as Mayor of Bristol and Chair of Core Cities UK, I have received some criticism for the time I have spent on international issues which some see as irrelevant to their everyday lives.

Of course, our starting point as local leaders needs to be to improve the lives of our citizens.

But global events impact upon the lives of our citizens all the time. Whether directly, like the people who are coming to me and my fellow city leaders concerned about friends and family suffering in Sudan, Syria or Ukraine, or indirectly, for example responding to the urban heat challenges we saw last summer where sustained temperatures of 28 degrees were enough to buckle light rail tracks.

So many of the issues discussed at the G7 are not that remote or removed from our citizens’ daily lives. That is why it is vital that city leaders input into international frameworks and global processes.

The first responsibility of local leaders will always be to the places they represent, but we must recognise that cities’ international importance will only grow as the 21st century progresses.

Our cities fully deserve their place on the world stage and as Core Cities leaders we will continue to advocate for this.