Pope Francis on Thursday (January 9) stepped up his recent criticisms of Israel's military campaign in Gaza, calling the humanitarian situation in the Palestinian enclave "very serious and shameful."

In a yearly address to diplomats delivered on his behalf by an aide, Francis referenced deaths caused by the winter cold in Gaza, where there is almost no electricity.

The pope, 88, was present for the address but asked an aide to read it for him as he is recovering from a cold.

The comments were part of an address to Vatican-accredited envoys from some 184 countries that is sometimes called the pope's 'state of the world' speech. The Israeli ambassador to the Holy See was among those present for the event.

Pope Francis said :

''Similarly, I renew my appeal for a ceasefire and the release of the Israeli hostages in Gaza, where there is a very serious and shameful humanitarian situation, and I ask that the Palestinian population receive all the aid it needs.

''War is always a failure. The involvement of civilians, especially children, and the destruction of infrastructures is not only a disaster but essentially means that between the two sides, only evil emerges as the winner. We cannot in any way accept the bombing of civilians or the attack on infrastructures necessary for their survival. We cannot accept that children are freezing to death because hospitals have been destroyed or a country’s energy network has been hit.''