Nissan has again warned that its Sunderland plant could lose production of one of its most important cars if the UK continues to stay outside the euro, the BBC reported on its website.

The report noted that the Wearside facility currently makes the company's mid-sized Almera model [as well as the Primera and Micra], but Nissan says it may now produce the forthcoming replacement [which will share its platform with 44.4% shareholder Renault's Megane] in France.

Carlos Ghosn, the company's president and chief executive, reportedly made the threat at the Detroit motor show, adding it would be "relatively easy" to switch to the continent, the BBC said.

The Nissan factory began making cars in 1986 and this is not the first time Ghosn has threatened to move UK production to France since Renault took a controlling shareholding in the Japanese firm.

The BBC noted that Nissan's threat to move production of the Almera replacement to France may mean the UK government steps in with a financial package - this happened two years ago when it came up with some £40 million to keep production of the redesigned Micra supermini model at Sunderland.

Yet Ghosn, who expressed frustration at what he sees as the government's slow movement on the euro, said production of the Almera replacement would definitely remain on Wearside if the euro was adopted, the BBC added.

"If the UK is in the euro system it is a no-brainer," he reportedly told the Financial Times. "We will stay."

The BBC also noted that Ghosn's comments come at a time when the Sunderland plant, the largest car production facility in the UK [and one of the worldwide motor industry's most productive], faces the possibility of its first ever strike.

Members of the Amicus union at the facility have voted to strike in protest at the Japanese firm's plans to transfer its 60-strong purchasing department from Sunderland to Cranfield, Bedfordshire - 200 miles away, the BBC report added.

Nissan has a large R&D operation at Cranfield where it designs and engineers its European model lines.

The report said the union complained that the workers were not consulted over the transfer and had been treated like "robots"though Nissan, which employs 4,500 in Sunderland, responded that it had offered an extensive relocation package for those workers who wanted to move.

Management and unions have been holding talks in an effort to avert the strike at a plant that has enjoyed 18 years of industrial peace, the BBC added.