One of Northern Ireland's largest employers, Wrightbus, has gone into administration.

The Ballymena-based bus builder has been facing serious financial problems and the move, which was announced by management, has seen 1,200 staff given redundancy notices.

Unions at Wrightbus were briefed by managers this morning.

There had been negotiations with potential buyers but no deal was reached.

Shortly after being told the news, devastated workers leaving the factory spoke of their shock and anger.

In addition to the staff directly employed by Wrightbus, unions say a further 1,700 jobs in the supply chain will be affected.

Unions say they remain confident that a buyer can be found for the business, and have urged the British government to intervene.

Joint administrator, Michael Magnay said: "It is bitterly disappointing for all concerned that despite extensive efforts over recent months it has not been possible to find a buyer who wanted to maintain the business as a going concern.

"The joint administrators will explore all remaining options for the business and assets, and would encourage any parties with an interest to contact them."

Susan Fitzgerald of the Unite trade union said there was "huge anger" in Ballymena over Wrightbus entering administration.

Speaking on RTÉ's News at One, Ms Fitzgerald said the workers at the Co Antrim plant are among the most highly-skilled workforces in Northern Ireland.

She said they were producing a product that is needed in society and there was massive potential for producing green, environmentally friendly buses.

Ms Fitzgerald urged the British government to intervene to save the company and called for transparency from Wrightbus over the events leading to the company entering administration.

She also said she believed that there were investors who were interested in the facility.

Chief Executive of the Northern Ireland Chamber of Commerce, Ann McGregor, described the fate of Wrightbus as "absolutely devastating for the firm's highly skilled workforce, for Ballymena and for the wider Northern Ireland manufacturing sector".

"It also has huge consequences for the firm's supply chain, especially SMEs. All efforts must be made to find a buyer for the company," she said.

"Without a sensible and pragmatic plan to support the sector and the urgent restoration of powersharing at Stormont, manufacturing, and the wider business community, will find itself in an even more challenging position.

"We have to find a way to stop the Northern Ireland economy losing any more ground."

Customers of Wrightbus include London and Dublin Bus

British Prime Minister Boris Johnson was one of the the company's most high profile customers during his time as mayor of London.

In 2012 he ordered a fleet of double deckers, which quickly became known as Boris buses.

The company also built virtually all of the 1,000 vehicles used by Dublin Bus, as well as around two thirds of Translink's fleet in Belfast.

Meanwhile, DUP MP Ian Paisley has met unions, management and employees and said administration is inevitable.

He told the BBC: "Essentially, from this point the administrator has a week to find a buyer".

Stormont Assembly member Jim Allister said it was devastating news and the heart had been ripped out of Ballymena.

"The rollercoaster ride of the last few weeks has added to the torment brought to the management and employees.

"For decades Wrightbus has been a constant and provider of thousands of jobs.

"Amidst the sadness of today I want to salute Sir William Wright for the vision and commitment which he brought in building up this company and providing good income for so many. He did not deserve this tragic outcome.

"However, Wrightbus has a great product. The combined efforts of us all must be to ensure that it does not become a fading memory but obtains a flourishing new beginning."