Mexico says its crackdown on border crossers has led to a 56% plunge in undocumented migration to the U.S. border over the last three months.

The drop comes after President Trump threatened to slap steep tariffs on Mexican goods if it did not do more to curb the flow of migrants from Central America.

“I do not think there will be a threat of tariffs because there is a 56% reduction,” Mexico’s foreign minister, Marcelo Ebrard, said at a Friday press conference.

Ebrard will meet in Washington with Vice President Mike Pence and Secretary of State Mike Pompeo on Tuesday, when he will review the results of Mexico’s 90-day border crackdown — and will plead for a tariff reprieve.

But, he said, he would not agree to some of the Trump administration’s demands, including a proposal that would force Mexico to accept asylum applications from any migrant who makes it to the country.

“The Mexican strategy is working. We will not agree to be a safe third country,” Ebrard said. “It goes against our interests.”

Instead, he said, he will push Washington to fulfill its economic aid commitments to Central America as a means of fighting undocumented migration.

“The United States promised $2 billion, but we’re still waiting for … a little more than $1 billion” of that, Ebrard said.

US Customs and Border Protection has not yet published data on migrant apprehensions at the border for August, but July numbers point to a 43% reduction in the flow of migrants from a high of 144,000 border crossers in May.

The Trump tariffs, which could have been as high as 25%, would likely have huge implications for Mexico, which sends about 80% of its exports to the United States.

To head them off, Mexican President Mexican President Andres Manuel Lopez Obrador deployed 25,000 troops to Mexico’s northern and southern borders in a bid to stem the flow of border crossings into the US.

He has also denied transit visas to hundreds of African migrants massed in southern Mexico — stranding them there instead of allowing them to travel north to the US border.

“We will not budge,” Lopez Obrador said last week, when the Africans protested. “We cannot do that. It isn’t our job.”