European leaders have expressed concerns over the outcome of Italy’s election and condemned a senior politician who warned that the “white race” was at risk from uncontrolled immigration.

Brussels is concerned about the increasingly xenophobic tone of the campaign for the March 4 general election, as leading parties spar over immigration in a country which has rescued 600,000 migrants and refugees in the Mediterranean in the last four years.

Attilio Fontana, a prominent politician from the Right-wing Northern League, apologised for his remarks about the threat of migrants, in which he said: “We have to decide if our ethnicity, if our white race, if our society continues to exist or if it will be canceled out.”

“It was an unfortunate expression,” Mr Fontana, who is the League’s candidate to become the next governor of the rich northern region of Lombardy, said on Wednesday.

But he stood by his warning over the impact of the hundreds of thousands of migrants and refugees who have reached Italy by boat from Libya.

"I think that this uncontrolled immigration risks causing serious problems for our country in the future. This is what I wanted to say,” said Mr Fontana, a former mayor of the northern town of Varese.