* Northern League's Calderoli eventually apologises
* Prime Minister Letta says comment "unacceptable"
* Kyenge urges him to reflect on his language
A senior parliamentarian in the anti-immigration Northern League party likened Italy's first black minister to an orangutan and only apologised on Sunday after a storm of criticism.
Cecile Kyenge, an Italian citizen born in the Democratic Republic of Congo, has been the target of repeated racial slurs since her appointment as integration minister in April.
Roberto Calderoli, vice president of Italy's Senate, said on Saturday at a political rally in the northern town of Treviglio: "I love animals - bears and wolves, as everyone knows - but when I see the pictures of Kyenge I cannot but think of, even if I'm not saying she is one, the features of an orangutan."
He said the success of Kyenge encouraged "illegal immigrants" to come to Italy, and she should be a minister "in her own country", according to media reports.
Politicians, including some from his own party, lambasted Calderoli, with some calling for him to resign as Senate vice president. In an official statement and on Twitter, Prime Minister Enrico Letta said the comments were unacceptable.
"They go beyond all limits. Full solidarity and support to Cecile. Forward with your and our work," Letta said.
For most of the day, Calderoli said he had no intention of resigning and offered only a qualified apology.
"I did not mean to offend and if minister Kyenge was offended I am sorry, but my comment was made within a much broader political speech that criticised the minister and her policies," he said.
But after hours of nearly universal condemnation and extensive coverage by the international media, Calderoli called Kyenge in the evening to apologise directly.
"I just spoke with minister Kyenge and I apologised," Calderoli told state news agency Ansa.
Kyenge is campaigning to make it easier for immigrants to gain citizenship, and she backs a law that would automatically make anyone born on Italian soil a citizen.
Last month, a Northern League member in the European parliament was expelled from the eurosceptic Europe of Freedom and Democracy group for making racist remarks about her.
Mario Borghezio had attacked Kyenge for wanting to impose "tribal traditions" in Italy as a member of a "bonga bonga" government, an apparent play on the so-called "bunga bunga" parties of former Prime Minister Silvio Berlusconi.
Opposition politician Calderoli, twice a cabinet minister under Berlusconi, has often caused offence.
In 2006, he was forced to resign as reform minister after displaying a T-shirt mocking the Prophet Mohammad during a state news broadcast. The same year, after Italy won the soccer World Cup, he disparaged the opposing French team, which he said had lost because its players were "niggers, Muslims and communists".
Before Calderoli's apology, Kyenge told AGI news agency he should think of his responsibility as a senior Senate member.
"I don't want to address Calderoli the person, but as a representative of an institution: reflect on what you want to represent through your language," she said.