The Vatican’s chief spokesman, the Rev. Federico Lombardi, said the pope had postponed several appointments and was resting.

“There is nothing to worry about,” Lombardi said. “His life has been very intense in the past few weeks. It is totally normal for the pope to rest.”

Lombardi said 77-year-old Francis would be well enough to attend his general audience Wednesday.

Francis has set a frantic pace since he was elected pope last year, and his schedule intensified in recent weeks he traveled to the Middle East on a demanding three-day official visit. After celebrating Pentecost Sunday, he hosted the Israeli and Palestinian presidents for a momentous Vatican prayer summit Sunday evening.

Vatican officials have privately expressed concern at the pope’s heavy workload, particularly since he had a portion of one lung removed as a young man. Italian media reports have also suggested he has suffered from back pain recently.

After meeting Israeli President Shimon Peres and Palestinian President Mahmoud Abbas on Sunday, the pope had a busy morning of engagements Monday, including a meeting with Cardinal George Pell, who heads the Vatican economic secretariat.

While it is customary for popes to take a break during the summer and leave Rome for the palace at Castel Gandolfo, Francis has chosen to stay in Rome and work, even as his closest advisers are pushing him to take a vacation.

Francis is planning to visit South Korea from Aug. 13-18 and is expected to visit Sri Lanka and the Philippines for a two-day visit in January.