One of the world’s largest offshore wind farms has been approved by the Scottish government despite concerns from conservationists that it could kill tens of thousands of seabirds.

The Berwick Bank project – to be positioned 23 miles off the east coast in the North Sea – could generate enough electricity to meet the annual energy needs of every household in Scotland twice over.

Conservation groups had urged rejection of the scheme over its impact on seabirds in the area and called it a “very dark day for seabirds”.

Deputy First Minister Kate Forbes said the approval had been given after “extremely careful consideration”.

Located about 23 miles (38km) from the important seabird colonies of the St Abb’s Head National Nature Reserve and the Bass Rock, developers SSE Renewables want to construct up to 307 turbines.

The project prompted five charities, led by RSPB Scotland, to urge ministers to reject the plans which it is predicted will kill tens of thousands of seabirds.

The Scottish government said the approval was subject to the company producing a detailed seabird compensation plan outlining how any adverse impact would be tackled.

That plan will need to be approved by Scottish ministers ahead of the project proceeding.

Kate Forbes said: “The decision to grant consent to Berwick Bank is a major step in Scotland’s progress towards achieving net zero and tackling the climate crisis, as well as supporting national energy security and growing our green economy.”

She said it was also an important decision for the renewables sector and the government would continue to work with developers to “balance the needs of people and nature”.

UK Energy Secretary Ed Miliband said: “We welcome this decision which puts us within touching distance of our offshore wind targets to deliver clean power by 2030 – boosting our mission to make Britain a clean energy superpower.”

He said it marked a “huge step forward in Britain’s energy security and getting bills down for good”.

Scottish Secretary Ian Murray said the project had the potential to make a “huge contribution to the UK government’s growth and clean energy missions and create clean power jobs in Scotland”.

He said it underlined the “massive potential” clean energy had to “generate jobs, wealth and opportunity for Scottish families”.

SSE Renewables said the project had the potential to create thousands of jobs and inject £8.3bn into the economy over its lifetime.

Managing director Stephen Wheeler said the consent was “hugely welcome”.

He said the project could “rapidly scale-up Scotland’s operational renewable energy capacity” and help deliver “homegrown, affordable and secure clean energy”.

However, Anne McCall, director of RSPB Scotland, described it as a “very dark day for seabirds”.

“It is a terrible decision on a really bad development,” she said.

“Berwick Bank would be catastrophic for Scotland’s globally important seabirds which are already facing alarming declines.

“In addition, its impacts are so damaging they will make the relative impacts of other windfarms significantly higher.”

She said she feared the consent could “catapult some of Scotland’s most-loved seabird species towards extinction”.

She stressed they supported offshore wind but “in the right locations”.

The National Trust for Scotland’s Diarmid Hearns said the decision was “deeply disappointing”.

“More than that, we fear it will also be the cause of significant harm to the seabird colonies of St Abb’s Head national nature reserve and elsewhere on the coastline,” he added.

“As we observed in our submission, the proposed mitigations by the developers fell far short of alleviating the expected impacts in terms of fatalities and disruption.”

He said they would be monitoring bird populations at the reserve and would report any impact.

The news came just days after President Trump launched the latest in a series of attacks on the move towards using wind turbines to generate electricity.

Speaking on his visit to Scotland, he said: “You fly over and you see these windmills all over the place, ruining your beautiful fields and valleys and killing your birds, and if they’re stuck in the ocean, ruining your oceans. Stop the windmills.”

The president is a long-standing critic of turbines, having fought and lost a long battle at Holyrood and in the courts to prevent a wind power development being built in the North Sea off Aberdeen.

Trump argued that the project, which included 11 wind turbines, would spoil the view from his golf course at Menie.