With Britain leaving the European Union, its neighbours and historic trading partners in Flanders think it is time to revive efforts to forge a new North Sea union to tighten links around shared waters.

Geert Bourgeois, prime minister of the autonomous region that is home to more than half Belgium’s population, said on Wednesday (24 August) he will seek agreements with other littoral states and regions to promote cooperation on managing resources such as energy and fisheries, as well as research and development.

Acknowledging that similar initiatives in recent years to strengthen ties among Britain, Belgium, the Netherlands, Germany, Denmark, Sweden and Norway had failed to take off, Bourgeois said that was partly because all of those except Norway already shared EU status.

“The reaction was lukewarm … as we thought there was no need for another international organisation,” he told Reuters.

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But that, he believed, has changed with the British vote to leave the bloc, turning the western coast of the North Sea eventually into non-EU territory: “Now that Britain is also leaving it would be good to work on such a union.”

There is an existing EU programme which supports projects that straddle local authority regions around the North Sea and Bourgeois, from the centre-right Flemish nationalist party N-VA which also sits in the Belgian federal coalition, said there was no intention to duplicate EU activities in the area.

But a specific North Sea Union could intensify cooperation and promote economic development. The Flemish government has already estimated in the wake of the Brexit referendum that trade disruption and other effects could lop 1.8-2.5% off Flanders’ economy once Britain leaves the EU.

Bourgeois compared his proposal to the Union for the Mediterranean, founded in 2008 on the initiative of then French President Nicolas Sarkozy to bring together the EU and Balkan states to the north with Arab countries, Turkey and Israel.

However, regional conflicts have hamstrung the UfM and some critics have said it has become an expensive “talking shop”.