The Defence Secretary says "he will not tolerate" anyone being let back into the British military if they have been dismissed for drug use.
It is after it was confirmed former Army troops axed for illegal drug offences have been paid to return to service in "specialised roles".
Gavin Williamson told Forces News on Monday: "Let’s be absolutely clear – anyone caught taking drugs can be and should expect to be dismissed from the Armed Forces.
"We are not going to be letting anyone back into the Armed Forces if they have been dismissed for taking drugs.
"This is something that I will not tolerate and something I do not want to see.
"If people have been dismissed from the Armed Forces for taking drugs, they don’t have a future in back in the Armed Forces.
In a statement an Army spokesperson said: "Neither the Army, or its recruiting partner Capita, have directly approached individuals to invite them to re-join the Armed Forces.
"However, we always welcome applications from individuals whose circumstances have changed since leaving our ranks.
"Financial incentives to return have been offered to fewer than 10 people since the start of the scheme in April, and only where there is a clear need to fill highly skilled or specialist roles.
"In no way is this connected to an individual's reason for leaving the Army, and anyone applying to re-join after previously failing a drugs test must pass a new test in order to be accepted."