Rene Angelil's accuser has now been charged with trying to extort $13.5m (£8.3m) from the couple.

Yun Kyeong Sung Kwon had alleged that Mr Angelil raped her in a Las Vegas hotel room in March 2000.

Mr Angelil, 61, who acts as Dion's manager, had always vehemently denied the allegation.

Dion is due to perform a residency in Las Vegas

Police said they had decided not to pursue the case because of lack of evidence.

"The case against Mr. Angelil is officially closed," said Lieutenant Jeff Carlson, of the Las Vegas police department.

Ms Kwon, 47, had claimed that Angelil followed her into the hotel lift against her will, sexually molested her and then raped her in her room.

But she and her husband Ae Hoe Kwon, 50, were arrested on Thursday on charges of extortion, conspiracy to commit extortion against the couple, and bribing a witness.

They were charged and were in custody in a Las Vegas jail, said police Lieutenant Ted Snodgrass.

Dion and Angelil have a young son

He said: "The couple went into the offices of the criminal lawyer of Mr Angelil in Las Vegas and made demands for a large sum money or they were going to reveal certain information regarding Mr. Angelil's rape case."

Ms Kwon is also accused of failing to pay casino bills of about $500,000 (£309,000) and faces four charges of passing bad cheques.

Mr Angelil has represented Dion, 34, since the globally-successful singer was 12.

The couple married in December 1994 and their son Rene-Charles was born in January 2001.

Dion is due to begin a three-year engagement at Caesars Palace in Las Vegas in March.