A British secession from the European Union in next month’s referendum could have disastrous economic consequences, G7 leaders warned today at the close of a summit in Japan.

The grouping is the latest to sound the alarm over the possibly far-reaching dangers of one of the continent’s largest economies opting to go it alone.

“A UK exit from the EU would reverse the trend towards greater global trade and investment, and the jobs they create, and is a further serious risk to growth,” they said in a declaration after talks largely focused on kickstarting the world economy.

The comments highlight international concern over the possibility of so=called “Brexit”, as British voters prepare for a June 23 referendum to decide whether to leave the 28-country bloc.

Leaders and ministers from the powerful Group of Seven democracies reiterated their concerns in Japan, although they were careful to stress that the decision was up to the people of Britain.

“This summit is sending the signal that all of us hope that Great Britain remains a member of the European Union,” German Chancellor Angela Merkel said, after meeting with her counterparts from Britain, Canada, France, Italy, Japan, and the United States.

“But of course the decision has to be made by the British voters,” she added.

UK Prime Minister David Cameron has been campaigning for Britain to stay in, with recent polls suggesting a widening lead for supporters of continued EU membership.

‘Leave’ campaign

However, the “leave” campaign is putting up stiff competition, with a number of high-profile supporters, including former London mayor Boris Johnson.

They have sought to tap into discontent over what is popularly seen as the EU’s tendency to overreach, which many in the island nation see as a threat to its distinct identity.

However, opponents of Brexit say a vote to leave the EU would spark political and economic turmoil for the region, which could spread to other parts of the world.

They warn global selloffs and violent currency fluctuations could follow.

They say the reduction in inward migration that the “out” camp wants would leave Britain short of plumbers, builders, mechanics and waiters, crimping the economy.

It would also force white collar jobs from London, with bankers and lawyers decamping to rival financial capitals such as Frankfurt or Paris.

The International Monetary Fund has warned of a potentially severe global market reaction to a “Leave” vote, while G7 finance ministers at a meeting earlier this month warned of the prospect of a global “shock”.