Carlos Ghosn vowed yesterday to “fight hard” to keep Nissan’s car plant in Sunderland competitive, despite the costs arising from Britain’s failure to join the single European currency.

His comments came weeks after Takeo Fukui, the president of Honda, Nissan’s arch rival, said that the decision to build its car plant in Swindon had been a “mistake” because Tony Blair had not taken the UK into the eurozone.

“You cannot build a plant based on foreign exchange - that makes no sense,” said the executive credited with enginnering Nissan’s turnaround from near-bankruptcy seven years ago. “It is going to be there for 50 years. It is only in a really, really tragic situation that a car manufacturer is going to take action against an asset in a country where he has developed competences, skills and intellectual property.”

The Brazilian-born chief executive of both Renault and Nissan also predicted an era in which the Sunderland car plant - along with the rest of the automotive industry - would remain competitive only by sourcing almost every component from manufacturers in lower-cost countries.

As Nissan pushes further into China and other “challenging” emerging markets, Mr Ghosn said, one of his central missions would be to craft a company culture in which “people consider it totally normal for unpredictable things to happen . . . and are able to react.”

Nissan’s net profits stumbled 11 per cent in fiscal 2006, while its local rivals Toyota and Honda continued to advance.

Mr Ghosn’s promise that the market would be shown the company’s new business plan a year from now did little to improve overall sentiment, although several analysts have sharply upgraded the stock in recent days. Last week’s announcement that the entire board would forgo bonuses this year to atone for the shrinking margins restored a further degree of respect.

Although Mr Ghosn insists that his changes at Nissan have changed the company’s culture once and for all, long-term observers wonder whether elements of “bad old Nissan” may be creeping back in. He acknowledges that Nissan’s stock may trade at a discount because the market is subconsciously nervous of the possibility - which he firmly denies - of Mr Ghosn leaving after eight years in charge.

The shares of Renault, he points out, have nearly doubled in value since 2005 because he has run that company for only two years, and investors assume he will be around for a while. “The probability of the company going back to being old Nissan is remote,” he says, “but there are pockets of conservatism coming back.”

Pledging to fight that trend, he partly blames the 2006 profits warning on old Nissan-style “political games played within he company” and on “commitments taken that were not as pure as they used to be”.

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