President Trump speaks with Prime Minister of Italy Giuseppe Conte during a joint press conference in the East Room at the White House on Monday. (Jabin Botsford/The Washington Post)

President Trump on Tuesday seized on news reports of a higher murder rate in Mexico than previously reported to bolster his threat to shut down the government if Congress fails to meet his demands for border-wall funding and other immigration measures.

“One of the reasons we need Great Border Security is that Mexico’s murder rate in 2017 increased by 27% to 31,174 people killed, a record!” Trump wrote on Twitter. “The Democrats want Open Borders. I want Maximum Border Security and respect for ICE and our great Law Enforcement Professionals! @FoxNews”

His tweet referenced a report Monday by the Mexican National Institute of Statistics and Geography, which revised a previous homicide count of 25,339 for 2017. With the higher figure, the rate of homicides in Mexico was the highest since at least 1990.

Trump fired off his tweet as the issue was being discussed on Fox News’s “Fox & Friends.”

Senate Majority Leader Mitch McConnell (R-Ky.) and House Speaker Paul D. Ryan (R-Wis.) have laid out a strategy to fund more than half of federal agencies by a Sept. 30 deadline. That would punt some of the more contentious fights — including money for Trump’s long-sought U.S.-Mexico border wall — until after the elections.

But demands by Trump, voiced as recently as during a news conference Monday, have put those well-laid plans in doubt.

“If we don’t get border security after many, many years of talk within the United States, I would have no problem doing a shutdown,” Trump said at the joint news conference with the visiting Italian Prime Minister Giuseppe Conte.

Trump also tweeted praise Tuesday for conservative broadcaster Rush Limbaugh, calling him “a great guy who truly gets it!”

During his radio show on Monday, Limbaugh praised Trump for his backbone in standing up to congressional leaders over a possible government shutdown in October.

“Trump is showing he’s not afraid of a government shutdown — which, believe me, the base of this party loves. The base of the Republican Party,” Limbaugh said. “They hate giving up every policy idea in the face of the blackmail of the government shutdown. So they loved Trump saying he’d be willing to do it over this because the issue of immigration is what got him elected.”

To date, Trump has not received from Congress as much funding as he has requested for his proposed wall along the Mexican border.

Trump also has been advocating for a number of changes to immigration laws, including ending the visa lottery program as well as “catch and release” — the practice of releasing from detention immigrants caught entering the country illegally if they agree to court hearings.

Seung Min Kim contributed to this report.