Airport security chiefs may have thought they had enough to worry about with shoe bombers, underpants bombers and people who forget to put their toothpaste into those little plastic bags. But, if so, they were reckoning without Benedict XVI.

At a meeting in the Vatican at the weekend, the pope made an authoritative – if entirely unexpected – incursion into the raging debate over the planned use of airport body scanners. He told an audience from the aerospace industry that, notwithstanding the threat from terrorism, "the primary asset to be safeguarded and treasured is the person, in his or her integrity".

Respect for the principles he enunciated "might seem particularly complex and difficult in the present context", he told his audience, which included airport managers, airline executives, security workers, pilots, cabin and ground staff.

They had to contend with problems arising "from the economic crisis, which is bringing about problematic effects in the civil aviation sector, and the threat of international terrorism, which is targeting airports and aircraft". But, he warned: "It is essential never to lose sight of respect for the primacy of the person."

The pope's words will delight civil liberties campaigners opposed to a device that strips passengers virtually naked.

But those involved in airport security will no doubt point out that, when he himself travels — on Alitalia – the pope and his entourage are simply waved through security controls.

An exception was in 1984 when a permanently installed detection mechanism in Luxembourg alerted security officials to the fact that John Paul II and his aides were packing significant quantities of metal. It had been activated by their crosses.