Michael Fallon, Defence Secretary of the UK, said on Thursday that British air strikes have killed around 330 ISIS militants from September of last year till the end of last month.
"This figure is highly approximate, not least given the absence of UK ground troops in a position to observe the effects of strike activity. We do not believe there have been any civilian casualties as a result of UK strike activity" said Fallon.
British citizens, Reyaad Khan and Ruhul Amin were killed in a drone strike, in Iraq on August 21. Junaid Hussain, one of the ISIS militants who hacked British Prime Minister Tony Blair's personal information was killed in a drone strike days later.
Downing Street, said the decision to use British drones to target individuals in Syria planning to commit terror attacks in the UK was taken “some months ago.”
National Security Council, which is presided by David Cameron, has stated that the drone strikes would be legal on the grounds of self-defence.
However, newly elected opposition leader Jeremy Corbyn has indicated that drone attacks are "legally questionable" and that violence should end in Syria and instead be replaced with "rapid political development."