Two British teenaged girls left a jail in Ghana on Thursday after a year in detention for trying to smuggle cocaine to Britain, prison officers said.

The girls, who were expected to fly out later on Thursday, would leave with "fond memories" of the West African country despite their time in jail, a spokeswoman for the pair said.

Yasemin Vatansever and Yatunde Diya, both then 16, were arrested in July 2007 at Ghana's main airport after Ghanaian drugs officers found 6 kg (13 lbs) of cocaine in two laptop bags they were carrying onto a flight to Britain.

The girls had told British TV they were tricked into carrying the bags and they did not know what was in them.

But drugs officers said they received 3,000 pounds each and accommodation and flights to carry the bags to Britain. They were convicted and sentenced in January to a year in jail. Their previous detention was offset against the sentence.

They left Maamobi Correctional Senior Centre prison in Ghana's capital Accra in a British High Commission (embassy) white diplomatic four wheel drive vehicle travelling at speed.

"They indicated they would never forget the hospitality and warm treatment they received while in prison," said Sabine Zanker, a representative of Fair Trials International who accompanied the girls during their release process and spoke on their behalf.

"They made such good friends and had promised to keep in touch with them, mostly through writing," Zanker told Reuters.

"They have a new life now and they very much look forward to making the best out of it."

Journalists waiting outside could not get close enough to see the girls through the windows, but senior prison official John Allotey and another prison officer who opened the gates for the car both confirmed the girls were inside.

A British High Commission official said on Wednesday the girls would be taken to the High Commission offices and flown back to Britain on an overnight flight later on Thursday.

A prison official told Reuters outside the jail that he had prayed with the girls before their release.

West Africa has become an increasingly important route in recent years for smuggling cocaine from Colombia to Europe, where street prices are generally higher than in North America.

Latin American drug gangs often pay people from impoverished West Africa to act as "mules", carrying their lucrative contraband to Europe in their bags or inside their stomachs wrapped up in condoms or plastic bags.

Vatansever and Diya were arrested under an operation set up in 2006 by the UK and Ghana to tackle drug smugglers using Accra airport as a gateway to Britain and Europe.

The length of the girls' sentences, handed down after recommendations from social services, was regarded as lenient as they could have faced three years in jail.