Michael has said that following his tour he was hoping for a quieter life
Singer George Michael has apologised for "screwing up again" after being cautioned for drug possession.
The star promised to "sort myself out" after he was arrested in a public toilet on Friday.
He was taken to a police station and given the caution for possessing class A and class C drugs.
"A 45-year-old man was arrested on 19 September on suspicion of possession of drugs in the Hampstead Heath area," a Metropolitan Police spokesman said.
In a statement Michael said: "I want to apologise to my fans for screwing up again, and to promise them I'll sort myself out. And to say sorry to everybody else, just for boring them."
The drugs were thought to include crack cocaine.
Home Office Minister Tony McNulty said drug laws needed to be "flexible".
Asked why Michael had been given a relatively mild punishment for the possession of class A drugs, Mr McNulty said he did not know the details of the case.
George Michael has been in trouble with police before
But he added that the law provides a wide range of punishments for possession of drugs, and "circumstances and context" had to be applied.
The Home Office website says possession of class A drugs can result in up to seven years in prison, an unlimited fine or both.
Mr McNulty told the BBC: "The biggest message is that drugs are wrong and people will be punished, but it must be right that there is flexiblity in the law."
But the government has the balance "about right" between being tough when it needs to be and providing treatment for individuals "to get off that horrible spiral of drug dependancy and crime", he added.
Last month, George Michael completed his 25 Live world tour, his first for 15 years.
After performing "final" dates at London's Earls Court and in Copenhagen, Michael said he would be retiring from arena and stadium shows.
He said he would leave the "bells and whistles" of large-scale tours behind after the tour because he wanted a "quieter life".
During the concerts, he performed his hit Outside in a police uniform in a jokey reference to previous arrests.
The song itself referred to his arrest in 1998 when he was detained by an undercover police officer for lewd conduct in a public toilet in Beverly Hills, California.
Until that time he had not "come out" in public, but the arrest and subsequent conviction forced him to reveal his homosexuality and his relationship with American Kenny Goss.
Michael also came into conflict with the law in October 2006 when he was found slumped over the wheel of his car.
And last May he was given a two-year driving ban after pleading guilty to driving while unfit through drugs.
Earlier this year, the 45-year-old singer signed a multi-million pound deal with publisher HarperCollins to write his autobiography, which he said would be a "no-holds barred" account of his life.
And during his final shows on stage, he revealed that he had written a Christmas song which would be released this December - his first festive song since Wham!'s Last Christmas, initially released in 1984.
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