A prison visitor thought he had found an ingenious method of smuggling herbal cannabis in when he tried to hide it in a bottle of banana milkshake.

But eagle-eyed CCTV staff spotted Hishack Palmer’s crafty ruse at HMP Swaleside and he was promptly arrested.

Despite being caught red-handed the 34-year-old drug addict denied possessing the cannabis with intent to supply.

After he was convicted it was revealed that he was jailed for 10 months in 2010 for committing a similar offence at Camp Hill Prison on the Isle of Wight.

The father-to-be, of Lovelinch Close, Peckham, south east London, was jailed for eight months for the latest offence.

"He has come in with the cannabis in his mouth. It was probably under his tongue or in the corner of his mouth"- Prosecutor Antony Hook

It means he should be out in time for the birth of his child in April.

Maidstone Crown Court heard Palmer was first given away by his body language, looking uncomfortable and agitated, when he arrived at the Eastchurch jail on July 16 last year.

A prison officer asked CCTV operators to watch him. They did so as he went to the cafe and bought two bottles of water and two milkshakes.

Prosecutor Antony Hook said Palmer took two quick swigs from one of the milkshakes.

As soon as he walked away from the till he was approached by three officers. They seized the drink and discovered the drug wrapped in plastic inside.

“He has come in with the cannabis in his mouth,” Mr Hook told the jury, who were shown the CCTV footage. “It was probably under his tongue or in the corner of his mouth.

“The reason he took a drink was to pass the drug into the bottle. His intention was to pass it to a prisoner.”

Following conviction, Mr Hook said Palmer first offended at the age of 13.

Said to have a long-standing cannabis habit, he was jailed for two-and-a-half years in 2001 for dealing in Class A drugs.

Rejecting a plea for a drug rehabilitation order to be imposed, Judge Philip St John-Stevens told Palmer: “Drugs being taken into prison do not just have a street value, but have a currency that becomes instrumental for extortion and undermines good order.”