The 130 workers at Belfast site where Titanic was built have been given redundancy notices

The historic Belfast shipyard that built the Titanic is expected to collapse into administration on Monday, threatening the end of centuries of shipbuilding in the city.

Harland and Wolff Heavy Industries, which dates back to 1861, has struggled in recent years as a result of stiff competition from overseas rivals. The company’s Norwegian owner, Dolphin Drilling, filed for bankruptcy in June and put the Belfast shipyard up for sale.

The company’s yellow cranes – named Samson and Goliath – have dominated Belfast’s skyline since 1974, but the workforce at the yard has declined from a peak of more than 35,000 in the 1920s to only 130 as Northern Ireland’s shipbuilding industry has all but disappeared. The remaining staff have been given redundancy notices.

As well as the “unsinkable” Titanic, which sank on its maiden voyage in 1912, the shipyard on the banks of the River Lagan made some of the world’s largest and most famous ships, such as the Titanic’s fleet mates, the Olympic and Britannic liners. The yard also played a key role in the second world war, producing warships such as HMS Belfast, the cruiser now moored on London’s South Bank as a floating museum.

The yard built its last ocean liner, the Canberra, in 1961, to take passengers from the UK to Australia. But Harland and Wolff gradually declined as the age of mass air travel supplanted travel by ship, and shipyards in east Asia offered cheaper vessels.

The yard has recently focused on repair work on ships and oil rigs and manufacturing the vast steel “foundation jackets” used on offshore wind turbines. However, in 2016 – the last year for which it has filed accounts – it slumped to a loss of £5.8m, compared with a £1.1m profit in 2015. Over the same one-year period the company’s turnover crashed from £67m to just over £8m.

A spokesman for Harland and Wolff said: “There has been a series of board meetings, the result of which is that administrators will be appointed.”

The accountancy firm BDO has been lined up to take over the business on Tuesday.

Facebook Twitter Pinterest A photograph of the Titanic in Belfast from a family album. Photograph: AP

The Labour party and the Unite union called for the shipyard to be nationalised, a move they claim would save the government money in lost tax revenues.

John McDonnell, the shadow chancellor, addressed Harland and Wolff workers at the site on Monday. He claimed Boris Johnson had failed the shipyard workers in his first real test as prime minister.

“We know this is a viable concern, we know the government has naval contracts it can put here to ensure the long-term future,” he said. “We know there are contracts out there but it just needs support from the government.

“I am saying to Boris Johnson very specifically he can’t stand on the sidelines.”

The bill for full nationalisation would reach millions of pounds, but a source with knowledge of the business said aid of only about £600,000 could have been enough to sustain the shipyard until the final quarter of the year, when it had hoped to win new orders. However, any such move could be viewed as illegal state aid under EU rules.

Potential new orders included a contract to develop the Ministry of Defence’s new Type 31e frigate – for which Harland and Wolff was part of a consortium bidding for the work – as well as multiple renewable energy contracts. The company was due to sign a contract understood to be worth as much as £80m on 12 August with the oil firm Suncor for upgrades to a floating oil storage vessel, the Terra Nova.

However, the government said last week the shipyard’s fate was “ultimately a commercial issue”. The uncertainty over the company’s future is thought to have hindered its ability to win new orders in recent weeks.

MJM Group, a Newry-based company specialising in boat fit-outs, and Flacks Group, a US buyer of struggling firms, have expressed their interest in buying the stricken business.

A person close to the talks said MJM appeared to be the frontrunner. MJM submitted a bid that was withdrawn a fortnight ago, prompting Unite to describe the firm as a “brand stripper” that would allow jobs to be lost while taking on the iconic name.

Workers at the site were scheduled to meet on Monday afternoon to discuss their options. They have occupied the yard in protest, and demonstrated outside Stormont during a visit by the new prime minister. The parliamentary majority of Boris Johnson’s government is reliant on the support of the Democratic Unionist party, whose MP Gavin Robinson represents the Belfast East constituency containing the yard.

Susan Fitzgerald, a regional coordinating officer at Unite, said employees had been treated as “little more than collateral damage to be cleared out”.

She added that the site contained many items of historic value, such as antique chairs, crystal glassware and pewter boxes used on the ships. Those artefacts belonged to the people of Belfast but could be lost in any sale, she said.

The decline of Harland and Wolff comes at a time when the entire Northern Irish economy – including a large manufacturing sector – faces an existential threat in a no-deal Brexit, according to Stephen Kelly, the chief executive of Manufacturing NI, a lobby group for the sector.

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Kelly described Harland and Wolff’s fate as a “failure of politics” in both Westminster and Stormont, where there has been no functioning elected government for more than two and a half years.

“The government has been either unable or unwilling to step in to see this firm through,” he said. “Given the iconic nature of the shipyard we can be pretty confident that, had there been a Northern Irish government in place, they would have been in a position to help.”

MJM has been contacted but has so far refused to comment on its intentions. Flacks Group declined to comment.