President Trump went on a Twitter tirade against Mexico and Democrats on Friday for not stopping the soaring number of migrants trying to enter the US — a day after threatening to slap a 5 percent tariff on Mexican imports over the issue.

“Mexico has taken advantage of the United States for decades. Because of the Dems, our Immigration Laws are BAD. Mexico makes a FORTUNE from the U.S., have for decades, they can easily fix this problem. Time for them to finally do what must be done!” Trump tweeted.

He also lashed out at Democrats over immigration.

“Hard to believe that with the Crisis on the Border, the Dems won’t do the quick and easy fix. Would solve the problem but they want Open Borders, which equals crime!” he raged in an earlier tweet.

He followed up with a pair of tweets accusing Mexico of having “taken” nearly a third of the US auto industry and claiming “90 percent” of illegal drugs entering the US come across the southern border.

The tweetstorm came after Trump, a self-described “Tariff Man,” announced the 5 percent levy on all Mexican imports starting June 10 and threatened to hike it to 25 percent on Oct. 1 if Mexico doesn’t do more to stop the flow of migrants.

Mexican President Andrés Manuel López Obrador fired back at the tariff threat and said he wanted to avoid a trade war.

“There is no need for confrontation,” he said on Friday.

The leftist president campaigned last year on a promise to decriminalize migration and said it was not Mexico’s job to do the US’s “dirty work” of deporting people.

And Trump’s threat also drew a withering response from some Republican lawmakers, who warned it could sink the revised NAFTA deal, the United States-Mexico-Canada Agreement.

“Trade policy and border security are separate issues,” said Sen. Chuck Grassley of Iowa, usually a Trump ally. “This is a misuse of presidential tariff authority and counter to congressional intent.

“Following through on this threat would seriously jeopardize passage of USMCA, a central campaign pledge of President Trump’s and what could be a big victory for the country.”

His Iowa colleague, Sen. Joni Ernst, also a Republican, warned that the tariffs could devastate farms states like hers and endanger the USMCA.

“The livelihoods of Iowa farmers and producers are at stake,” she said. “If the president goes through with this, I’m afraid progress to get this trade agreement across the finish line will be stifled.”

Senate Majority Leader Mitch McConnell (R-Ky.) was lukewarm on the tariffs, which would affect all Mexican imports, from avocados and beer to cars and car parts.

“As our third biggest trading partner, a healthy and vibrant economic relationship with Mexico is a vital source of our joint prosperity,” McConnell said. “Any proposal that impacts this relationship deserves serious examination.”

Analysts saw Trump attempting to distract from other news, including special counsel Robert Mueller’s first public statement on his Russia probe and reports that White House officials tried to keep the USS John McCain out of sight during Trump’s state visit to Japan.

“If there’s one thing Donald Trump knows, it’s how the press operates — and how he can manipulate it,” said Larry Sabato, head of the University of Virginia’s Center for Politics.

Crossings at the southern border have spiked this year despite Trump’s vow to crack down on illegal immigration.

More than 109,000 migrants were apprehended at border in April alone, and a record group of 1,036 was caught crossing into El Paso, Texas, Wednesday.