Former MI6 head Sir John Sawers
Former MI6 head Sir John SawersReuters

The former head of Britain's MI6 intelligence agency has said that he "agrees with the Pope" that people should avoid drawing pictures of Mohammed, and that if they do they can expect to provoke a terror attack.

Speaking for the first time since stepping down as head of MI6, Sir John Sawers told an audience in the Philippines that "There is a requirement for restraint from those of us in the West," according to Sky News.

"I rather agree with the Pope that, of course, the attacks in Paris were completely unacceptable and cannot be justified on any basis whatsoever, but I think respect for other people's religion is also an important part of this," he continued.

"If you show disrespect for others' core values then you are going to provoke an angry response. That doesn't justify anything, but I think we just need to bear it in mind."

Sawer's remarks were relating to a controversial speech by Pope Francis last week, in which he appeared to sympathize with - if not outright justify - the motives of the terrorists who murdered 12 people at the offices of the Charlie Hebdo magazine in Paris.

Saying there are limits to free speech, the pope referred to Alberto Gasbarri, who organizes his trips abroad.

"If my good friend Dr. Gasbarri says a curse word against my mother, he can expect a punch," the pope said half-jokingly, proceeding to throw a mock punch at him. "It's normal. You cannot provoke. You cannot insult the faith of others. You cannot make fun of the faith of others."

"There are so many people who speak badly about religions or other religions, who make fun of them, who make a game out of the religions of others," he said.

"They are provocateurs. And what happens to them is what would happen to Dr. Gasbarri if he says a curse word against my mother. There is a limit," opined the pope.

A Vatican spokesman later responded to the backlash that followed by insisting Pope Francis had not meant to justify the attacks.

In his talk, Sawer also emphasized the limits of the capabilities western intelligence and security services have in preventing terrorist attacks, saying it was impossible to catch every single terror plot.

"If I was to sit here and say will the goalkeepers of the security services and the police keep every single attempt to get the ball into the net, out? No. At some point these threats will get through and there will be another terrorist attack in this country."

He also weighed into the debate over internet and information privacy, warning that blocking intelligence agencies from certain areas would harm their ability to protect against attacks.

"If the technology companies allow to be developed, areas that are simply impenetrable, you're inviting problems," he said.