Britain's immigration minister has resigned after telling the prime minister his cleaner was an illegal immigrant who did not have permission to work in the country.
Mark Harper, who last year launched a controversial billboard campaign urging illegal immigrants to "go home", said on Saturday that he had employed the woman, who has not been named, on the basis of documents that she had provided him with.
There is no suggestion that Mr Harper knowingly employed an illegal immigrant.
In a letter to the prime minister, David Cameron, Harper wrote that he had hired the cleaner in April 2007.
"I was very mindful of my legal and financial obligations and undertook a number of checks beforehand...even though there was no legal requirement for me to check her right to work in the UK, I felt that it was appropriate to do so."
"When you appointed me as Immigration Minister I went through a similar consideration process and once again concluded no further check was necessary. In retrospect, I should have checked more thoroughly."
A government spokesman said: "Mark Harper offered his resignation after he was informed that his cleaner did not have indefinite leave to remain in the United Kingdom, despite having shown him documents claiming she did.
"He immediately notified the prime minister, who accepted his resignation with regret. There is no suggestion that Mr Harper knowingly employed an illegal immigrant."
As immigration minister, Harper was behind a divisive campaign to encourage illegal immigrants to turn themselves in to border authorities or face arrest.
The campaign, which was trialled in six London boroughs and earned the hashtag " #racistvan ", advertised a telephone helpline for those who wanted to leave the UK voluntarily.
A report published by the Guardian , however, showed that only 11 people left the country as a direct result of the advertisements and that of the 1,561 text messages received in response to the advert's invitation to text for free advice and travel documents, 1,034 were hoax messages that UK Home Office staff spent 17 hours dealing with.