Detailing an increasingly desperate situation in Venezuela, the United Nations made a confidential plea on Wednesday to the country’s two rival leaders to end a political battle over humanitarian aid that has blocked shipments of food and medicine.

A copy of a report delivered to representatives of both sides, obtained by The New York Times, casts no specific blame for worsening a crisis in Venezuela that by some estimates has plunged nearly the entire population of 32 million into poverty.

But it suggests that measures carried out by the government of President Nicolás Maduro, such as blockading Venezuela’s borders and imposing restrictions on aid organizations, have made the crisis more acute, as have sanctions put in place by the United States and others.