ROME — Pope Francis told ambassadors accredited to the Holy See on Thursday that he wasn’t up to delivering his annual foreign policy speech and asked an aide to deliver it instead.

A congested-sounding Francis began the speech, greeting the ambassadors gathered in the Hall of Blessings.

But just a few lines into the lengthy speech, which usually recaps highlights of the past year, the 88-year-old Francis said he was still battling a cold and handed the remarks over to an aide.

Francis, who had part of one lung removed as a young man, often suffers bouts of bronchitis in winter that leave him out of breath and make it difficult to speak at length. He has just emerged from a grueling Christmas period in which he inaugurated the Vatican’s Holy Year celebrations.

He has sounded congested in recent days but has nevertheless kept up with his typically busy schedule.