The German chancellor, Friedrich Merz, has said he wants the North Sea to become the “largest reservoir of clean energy worldwide”, as he announced plans to accelerate efforts to link up offshore wind power projects with Europe.

The UK and nine other European countries have agreed to accelerate the rollout of offshore windfarms in the 2030s and build a power grid in the North Sea, in a landmark pact to turn the ageing oil basin into a “clean energy reservoir”.

They will build windfarms at sea that directly connect to various countries through high-voltage subsea cables, under plans that are expected to provide 100 gigawatts (GW) of offshore wind power, or enough electricity capacity to power 143m homes.

Merz spoke as energy ministers from the UK, Belgium, Denmark, France, Germany, Iceland, Ireland, Luxembourg, the Netherlands and Norway met in Hamburg to sign a declaration making the commitment.

Under the pact, the governments have promised to collectively build 5GW of offshore wind capacity every year between 2031 and 2040 by helping to support private sector investments. In return, more than 100 companies have signed up to an industry declaration that promises to reduce costs and create 91,000 jobs.

The energy secretary, Ed Miliband, said the UK was “standing up for our national interest” by pushing for clean energy and getting “off the fossil fuel rollercoaster”.

Miliband told the summit: “We see it [as] absolutely in our national interest to not only pursue clean energy domestically at home, but to work with our European allies and friends on delivering it across the North Sea.”

“This clean energy security pact – the Hamburg declaration – is an incredibly statement, I think, of our shared commitment to make the North Sea a clean energy powerhouse,” he said.

The North Sea deal could help to attract €1tn (£867bn) in offshore wind investment by 2040 and would mark the day that Europe “doubles down on offshore wind”, according to Malgosia Bartosik, the interim chief executive of WindEurope, an industry association.

“This is the best possible response to those who doubt Europe and our drive to deliver energy that is homegrown, secure and affordable,” she said.

The pact comes less than a week after Donald Trump criticised the UK’s plans to phase out production of North Sea oil and gas, and complained about European wind power.

The US president told the World Economic Forum in Davos: “There are windmills all over Europe. There are windmills all over the place and they are losers. One thing I’ve noticed is that the more windmills a country has, the more money that country loses and the worse that country is doing.”

The UK also plans to work with Germany, Belgium, Denmark and the Netherlands to open up cross-border, offshore electricity projects, with a focus on joint planning and cost sharing.

The latest agreement reaffirms Europe’s commitment to wind power, after North Sea countries promised three years ago to build 300GW of offshore wind in the area by 2050. A new offshore wind power grid will contribute to this target. Last year, wind and solar overtook fossil fuels in the EU’s power generation, generating 30% of the bloc’s electricity.

Transmission grid owners from each country are expected to find about 20GW of “economically promising” cross-border projects by 2027 which could be rolled out in the 2030s. These could include “hybrid offshore projects”, such as an offshore windfarm in UK waters that connects to Britain and other countries to make electricity exports more efficient.

Energy UK, the sector’s trade association in Britain, said it fully backed the “landmark efforts … to transform the North Sea into a truly regional clean power hub”.

The UK government handed out record subsidy contracts this month for enough offshore wind projects to power 12m UK homes in a boost for its goal to create a clean electricity system by 2030. The most competitive UK auction to date granted support contracts to eight offshore windfarms worth £22bn which the government believes will support 7,000 skilled jobs and lower energy bills for good.

Miliband told delegates at the summit the declaration was “a very strong answer to the doomsters, the defeatists, the naysayers who have somehow wanted to write off offshore wind. Indeed, it was the largest offshore wind procurement in the history not just of Britain, but of Europe.”

Jane Cooper, the deputy chief executive of the trade body RenewableUK, said: “We will share infrastructure and data to enable clean power to flow more efficiently between our nations, and further integrate our electricity markets to drive down costs for billpayers,” she said.