A former British Army sergeant who tried to kill his wife by sabotaging her parachute has been sentenced to at least 18 years in prison.

South African-born Sergeant Emile Cilliers was convicted last month of two counts of attempted murder for the parachute tampering and sabotaging a gas valve at the couple's home.

READ: SA man guilty over wife's near death parachute fall in England

Victoria Cilliers survived falling 1 200 metres in April 2015 by landing on a newly plowed field.

Prosecutors said the 38-year-old defendant was deeply in debt and wanted his wife's life insurance money to pay off his bills and start a new life with his lover.

Cilliers was sentenced on Friday at Winchester Crown Court in southern England to life with no chance of parole for 18 years. Judge Nigel Sweeney told him "this was wicked offending of extreme gravity".