Pope Leo said Thursday that conflicts in the Middle East were raging with an unprecedented "diabolical intensity" and appealed for greater respect for international law, in comments to Catholic bishops and aid agencies operating in the region.

At a meeting in the Vatican, the pontiff said countries in the region were being "devastated by wars, plundered by special interests, and covered by a cloud of hatred that renders the air unbreathable and toxic."

"Today, violent conflict seems to be raging... with a diabolical intensity previously unknown," he said, adding that the humanitarian situation in the Palestinian enclave of Gaza was "tragic and inhumane."

Leo, elected May 8 to replace the late Pope Francis, appealed last month for Israel to allow more humanitarian aid to enter Gaza. He did not name Israel in his remarks Thursday.

The U.S.-born pope also did not directly address the recent 12-day war between Israel and Iran that also saw the United States bomb suspected Iranian nuclear facilities but he called for countries to show better respect for international law.

"It is truly distressing to see the principle of 'might makes right' prevailing in so many situations today, all for the sake of legitimizing the pursuit of self-interest," he said.

"It is troubling to see that the force of international law and humanitarian law seems no longer to be binding, replaced by the alleged right to coerce others," Leo added.