Just before the Rio Earth summit 25 years ago, John Major, in whose cabinet I then served as environment secretary, made a bold prediction: reducing Britain’s carbon emissions in line with recommendations of climate science would not, he said, harm our economy: “Our initial measures ... will bring a worthwhile economic payoff to the country, to business and to ordinary people.”

This was a controversial statement at a time when solar energy, for example, was a costly technology better suited to spacecraft than British rooftops. And indeed the argument can still be heard that reducing greenhouse gas emissions will ruin our economies – even that it will return us to a pre-industrial living standard.

A quarter of a century later, the approach that we took has been richly vindicated. As research published on Monday by the Energy and Climate Intelligence Unit demonstrates, in that period the average Briton has grown richer faster than citizens of any other G7 nation; at the same time, his or her carbon footprint has fallen faster than in any other G7 nation. While it would be stretching reality to argue that Britain’s economic success has been driven by its climate change policies, no one can seriously argue any more that our climate policies have generated economic harm.

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I would argue that there are three principal factors why Britain tops the G7 league in terms of growing our economy while reducing our carbon emissions. We started earlier than most, we have been consistent, and we have used market forces wherever possible. Certainly our decision now looks to have been a prudent investment. British companies in low-carbon goods and services already turn over an estimated £83bn per year; and with Brexit opening the door for a new era of free trade with major countries in Asia and Latin America, most of which are pursuing their own clean energy transitions, this sector has the potential to become a major engine of trade and growth.

When I was negotiating the UN climate convention 25 years ago, the reality was that we did not know what it would cost to fulfil the treaty’s goal of preventing “dangerous” climate change. Science had not clearly told us what degree of global warming would be “dangerous”; nor did any government have a fully fledged plan for reversing the upward tide of carbon emissions.

We acted in the absence of perfect information because we had to. Margaret Thatcher had warned world leaders three years previously that humanity was “changing the environment of our planet in damaging and dangerous ways”, and that the only route to curbing it was a global treaty that did not constrain economic growth – because only growing economies would be able to afford the investment necessary to restrain greenhouse gas emissions. To a certain extent, her global climate treaty was a leap of faith in both the probity and the innovative capacity of humankind.

Since 1992 science has shown us ever more clearly what “dangerous” climate change looks like. Meanwhile, evidence has been growing that a transition to a low-carbon economy is economically feasible, and will bring added benefits such as cleaner air in major cities. These two factors drove all governments to conclude the Paris agreement in 2015.

Figueres is to be commended for her vision. The rationale remains what the British government put forward 25 years ago

Globally, carbon emissions have remained flat for the past three years, even as the world economy has grown by 7.5%. China and India are fast reversing their previous policies of building greater fleets of coal-fired power stations. Replacing our own use of coal with gas and renewable energy has brought UK carbon emissions down to a level last seen during the general strike of 1926.

Yet neither these remarkable developments nor the Paris agreement will secure a stable climate. The latest science tells us that greenhouse gas emissions need to start declining by 2020 at the latest in order to give reasonable confidence that global warming will stay well below the 2C limit, the target governments adopted in Paris. So, having halted the once unstoppable tide, the next logical step is to reverse it – and quickly. This is the mission on which a new initiative launched by Christiana Figueres, until recently the UN’s top climate official, will embark this coming week.

Figueres is to be commended for her vision. The rationale remains exactly that which the British government put forward 25 years ago: thatunchecked, climate change presents unacceptable risks for the future. Fortunately these are not risks that we have to take. Britain has proved the doom-mongers wrong: economies can thrive while emissions fall. Now let us put our collective weight behind the Figueres initiative, and finish the job.