The pope surprised journalists yesterday by encouraging his followers not to breed "like rabbits" and instead practice "responsible" parenting.

During his return flight from the Philippines on Monday, Francis was asked to respond to the issue of Catholics having more children than is financially viable because of the Church's stance on artificial contraception.

"Some people think that – excuse my expression here – that in order to be good Catholics we have to be like rabbits," the pope replied.

"No. Parenthood is about being responsible. This is clear."

Francis affirmed the ban on contraception, but insisted that there are many Church-approved methods of regulating pregnancy. He recalled meeting a Filipino woman pregnant with her eighth child. "She said, 'I trust in God.' But God gave us the means to be responsible," he said.

The pope also condemned what he called the "ideological colonisation" of developing nations by Western countries, which he said are increasingly imposing birth control laws. "Every people deserves to conserve its identity without being ideologically colonised," Francis said.

On Friday, the pope told an audience in the Philippines that attempts to "redefine family" were a threat to society. Referring to the government's subsidy on birth control for women, Francis condemned "insidious attacks and programmes contrary to all that we hold true and sacred".

"The family is also threatened by growing efforts on the part of some to redefine the very institution of marriage, by relativism, by the culture of the ephemeral, by a lack of openness to life," he said.

The pope also clarified during Monday's flight that he did not intend to justify violence when he said a friend who insulted his mother could "expect a punch" in return.

Speaking of the terrorist attacks in Paris earlier this month, the pope told reporters on January 15: "You can't provoke, you can't insult the faith of others, you can't make fun of faith.

"You can't make a toy out of the religions of others," he added. "These people provoke and then [something can happen]. In freedom of expression there are limits."

Francis said yesterday that while violence is not justifiable, it is a human response to provocation.

"In theory we can say a violent reaction to an offence or provocation isn't a good thing, that one shouldn't do it. In theory we can say what [the] gospel says, that we should turn the other cheek. In theory we can say that we have the freedom to express ourselves," he said.

"But we are human. And there is prudence, which is a virtue of human coexistence. I cannot insult or provoke someone continually because I risk making him angry."

The pope's trip to the Philippines culminated with a record-breaking Mass for more than six million people in Manila.

Vatican officials said the number eclipsed the estimated five million worshippers who gathered at a Mass led by Pope John Paul at the same venue in 1995. There are around 80 million Catholics in the Philippines, making it Asia's most populous Catholic nation.