There is "no suggestion that Mark Harper knowingly employed an illegal immigrant", Downing Street have said.
The Immigration Minister has announced his resigned over the issue.
Number 10 said David Cameron had "accepted his resignation with regret".
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Police are appealing for information about two sisters aged 12 and five who went missing three days ago.
Senior medical staff have urged junior doctors and the Government to break the deadlock over the medics' long-running contract dispute.
A young girl has become an internet sensation after pictures emerged of her being attacked by a goose.