President Donald Trump talks with a U.S. Customs and Border Protection (CBP) Border Patrol Agent while participating in a tour of U.S.-Mexico border wall prototypes near the Otay Mesa Port of Entry in San Diego, California, March 13, 2018.

President Donald Trump lashed out against Mexico on Sunday ahead of bilateral immigration talks geared toward averting the imposition of escalating tariffs on Mexican imports set to take effect next week.

"Mexico is sending a big delegation to talk about the Border. Problem is, they've been 'talking' for 25 years. We want action, not talk," Trump wrote in a post on Twitter.

"They could solve the Border Crisis in one day if they so desired," he wrote. "Otherwise, our companies and jobs are coming back to the USA!"

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The taunts threaten negotiations scheduled this week. Trump on Thursday announced via Twitter that he intended to apply gradually increasing tariffs on Mexican imports starting June 10 at a rate of 5%. Trump said the tariffs will remain in place until illegal immigration into the United States from Mexico is halted.

Trump's surprise announcement tanked markets that were already falling on U.S.-China trade worries. On Friday, the major indexes closed down more than 1%, with the S&P 500 off by more than 6% for the month. Analysts have warned the tariff battles if left unresolved could spark a global recession within a year.

Mexican Foreign Minister Marcelo Ebrard is scheduled to meet with Secretary of State Mike Pompeo on Wednesday to discuss curbing immigration into the U.S. through Mexico. President Andres Manuel Lopez Obrador, elected last year, said Saturday that he expects "good results."

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Trump has seemingly tried to minimize expectations, though. In tweets earlier Sunday, Trump wrote that Mexico was an "abuser."

"It has been this way for decades," he wrote.

Given Trump's negotiating style, the verbal attacks on Mexico could give way to a more friendly negotiating posture.

Early in his presidency, Trump told his then-Secretary of State Rex Tillerson not to bother negotiating with North Korean leader Kim Jong Un, referring to the reclusive despot as "Little Rocket Man." The next year, Trump and Kim "fell in love," Trump said.

"I was really tough and so was he, and we went back and forth," Trump said at a West Virginia rally in 2018. "And then we fell in love, OK?"

Investors are eagerly awaiting whether Trump will have a similar change of heart in the case of Mexico, a country he singled out as early as his June 2015 announcement speech. At the time, Trump claimed that the country was sending rapists and drug dealers to the United States. The president has since made border security the rallying cry of his re-election campaign.

On Monday, the Mexican delegation is scheduled to provide more details about their negotiation activities during a morning news briefing.