Rome: Pope Francis has called for more people to donate their organs in a bid to stop illegal trafficking, but spoke out against the legalisation of the organ market, Rome’s mayor said on Saturday.

“The pope authorised me to say that in his view organ donation through generosity must be encouraged, but the commercial use of organs is immoral,” mayor Ignazio Marino said, after meeting with Francis on Friday.

“We need to explain that donating organs is a gesture of love. Each of us, for example, has two kidneys, and giving one of them to a relative or a person we love is a beautiful gesture. Entering into the spiral of trade and sales is a crime,” the pope said, according to Marino.

The meeting with Marino and a world delegation of transplant experts came as the United States debates whether or not to introduce financial incentives for organ donation, which could include reimbursing costs of travel for donors and lost wages, as well as providing long term health insurance.

Lengthy waiting lists, with thousands dying through a lack of organs, have lead some in the US to suggest the market for human organs should be legalised.

The Buenos Aires pope slammed those who profit from the poor to traffic organs, saying he had seen “many Argentine children with long scars on their backs because their families had sold one of their kidneys,” Marino said.

“Exploiting the poverty of a mother who sells a kidney to feed her children, for a few hundred euros, with that kidney then trafficked and sold on for hundreds of thousands of euros, that is a crime,” he said.

The Holy See did not publish a transcript of the audience.