ROME (AP) — Pope Francis remained in critical condition Monday but showed slight improvement in laboratory tests and resumed some work, the Vatican said, including calling a parish in Gaza City that he has kept in touch with since the war there began.

The pope has begun working again after he showed slight improvement days after initially being listed in critical condition. Pope Francis is battling double pneumonia and is in the early stages of kidney “insufficiency,” The Associated Press reported.

The Vatican says Pope Francis remains in critical condition but has showed slight improvement in laboratory tests. He has resumed some work activities, including calling a parish in Gaza City that he has kept in touch with since the war there began.

The Vatican's lead diplomat on Thursday criticised President Donald Trump's plan for the U.S. to displace Palestinians from Gaza and "take over" the territory, in the second rebuke of a Trump policy by a top Catholic official this week.

Pope Francis is responding “positively” to medical treatment for pneumonia, according to the Vatican, a week after the 88-year-old pontiff was hospitalized in Rome.