The Christian Democratic Union head of the populous western German state was talking about Nokia’s move of a factory away from Duisburg to Romania when he said, “In contrast to the workers here in the Ruhr area, those in Romania do not show up at seven in the morning for the first shift and stay until the end. Instead they come and go when they want, and don’t know what they are doing.”

His speech – at an election rally in Duisburg – was filmed and posted on Youtube by members of the rival Social Democratic Party. The Dortmund-based newspaper Westfälische Rundschau reported at the weekend that he repeated the quote two days later at a rally in Münster.

He also sketched out a remarkable strategy to attract the attention of potential Chinese investors to the region, saying, “And if we have to, then we will meet up with some Chinese at something at the town hall, and if they then don’t want to finally invest in Duisburg, then they will also be throttled – until they find Duisburg beautiful.”

The state secretary general of the Social Democratic Party, Michael Groschek said although Rüttgers liked to compare himself with previous minister presidents, his latest speeches showed, “once again, that this is just a pose.”

Head of the local Greens, Daniela Schneckenburger said, “That is really from the lowest drawer of populism.”

The Berlin-based German-Romanian Association also criticised Rüttgers, saying it was troubling that he was serving prejudices in such a populist manner, and that European solidarity should be expected from a state premier.

Rüttgers attracted fierce criticism during the 2000 state election for his slogan Kinder statt Inder – or “Children rather than Indians” – at a time when the government of the time was trying to attract well-qualified foreigners to immigrate to fill empty jobs in the high-tech sector.

He apologised on Friday for the Romanian remarks, saying, “I was standing in front of North Rhine-Westphalian workers, whose fabulous efforts are globally acknowledged and who have lost their workplaces due to bad decisions taken at company headquarters. I did not want to insult anyone, and if that happened, I am sorry.”