Nearly all of Puerto Rico remained blacked out Monday on the eve of a visit by President Trump — and the US Energy Department offered a grim forecast for the restoration of electricity.

Little more than 5 percent of electrical customers had service on the storm-ravaged island, according to officials — with the head of its power utility saying that number would rise to just 15 percent over the next two weeks.

Food and drinking water also remained in short supply, and the Federal Communications Commission said more than 88 percent of cellphone towers were out of service, a number virtually unchanged since Saturday.

Gov. Ricardo Rosselló said the government was in danger of running out of money because the economy ground to a halt in the wake of Hurricane Maria, which slammed into the island Sept. 20.

“There is no cash on hand,” Rosselló told the local El Nuevo Dia newspaper. “We have made a huge effort to get $2 billion in cash. But let me tell you what $2 billion means when you have zero collection: It’s basically a month government’s payroll, a little bit more.”

In the brightest development, Rosselló said more than 720 of the island’s 1,100 gas stations were back in business, with the average wait time less than an hour, down from six or seven hours just a few days ago.

Rosselló said “gasoline is getting here,” with around 1 million barrels of gas and 500,000 of diesel expected to arrive this week.

The Trump administration is preparing to ask lawmakers for $13 billion in new funding to help Puerto Rico, Texas and Florida recover from a series of powerful storms, congressional sources told Reuters.

The president said he and first lady Melania Trump will fly early Tuesday to Puerto Rico, where they’ll meet with first responders and some of the 3.4 million struggling residents.

While acknowledging the ongoing electrical and communications problems, Trump said it’s “amazing what’s been done in a very short period of time.”

“There’s never been a piece of land that we’ve known that was so devastated,” he said.

Trump also said he planned to sit down with Gov. Kenneth Mapp of the US Virgin Islands, noting St. Croix was so badly damaged that Mapp “is probably going to meet us in Puerto Rico.”

White House press secretary Sarah Huckabee Sanders said the administration had reached out to San Juan Mayor Carmen Yulin Cruz, who on Saturday criticized Trump’s response to the storm.

“She’s been invited to participate in the events tomorrow, as well,” Sanders said.

With wire services