The US president and Mexican counterpart are in a war of words on Twitter
The diplomatic rift between the US and Mexico has deepened after Donald Trump's administration suggested taxing imports from the southern neighbour to fund the controversial border wall.
Donald Trump wants to slap a 20% tax on all imports from Mexico, which would raise US$10bn (€9.37bn) a year and "easily pay for the wall", according to a White House spokesman.
Mr Trump has said US taxpayers will initially fund the wall, while insisting its southern neighbour will eventually "100%" foot the bill as he accused Mexico's President Enrique Peña Nieto of not treating America "fairly" and "with respect".
The two leaders had been scheduled to discuss the matter at the White House next week.
The war of words between the pair saw Mr Peña Nieto saying he would scrap the meeting after Mr Trump himself earlier threatened to cancel the talks.
The US president, who flew to Philadelphia to meet leading Republicans at a party retreat, tweeted: "The U.S. has a 60 billion dollar trade deficit with Mexico. It has been a one-sided deal from the beginning of NAFTA with massive numbers...of jobs and companies lost. If Mexico is unwilling to pay for the badly needed wall, then it would be better to cancel the upcoming meeting."
The U.S. has a 60 billion dollar trade deficit with Mexico. It has been a one-sided deal from the beginning of NAFTA with massive numbers...— Donald J. Trump (@realDonaldTrump) January 26, 2017
of jobs and companies lost. If Mexico is unwilling to pay for the badly needed wall, then it would be better to cancel the upcoming meeting.— Donald J. Trump (@realDonaldTrump) January 26, 2017
Mr Peña Nieto then hit back, tweeting: "This morning we have informed the White House that I will not attend the meeting scheduled for next Tuesday with the @POTUS."
Esta mañana hemos informado a la Casa Blanca que no asistiré a la reunión de trabajo programada para el próximo martes con el @POTUS.— Enrique Peña Nieto (@EPN) January 26, 2017
In a speech in Philadelphia, Mr Trump cast the cancellation as a mutual decision.
He said that "unless Mexico is going to treat the United States fairly, with respect, such a meeting would be fruitless, and I want to go a different route. We have no choice".
The relationship between the two countries has been strained since Mr Trump promised the construction of a 2,000-mile wall along the border with Mexico in a clampdown on illegal immigration.
In a televised message to his country, Mr Peña Nieto reasserted that Mexico would not pay a single peso towards it.
Mr Trump would need to get approval from Congress for any new funding for the wall - with costs estimated at US$6.5m (€6.09m) per mile for a single-layer fence by the Government Accountability Office.
Soon after the US commander-in-chief tweeted, House Speaker Paul Ryan said the wall will cost between US$12bn (€11.2bn) to US$15bn (€14bn).
He added he expected the move to get congressional approval by the end of September.
Former Mexican president Vicente Fox Quesada, who has repeatedly attacked the idea of a barrier, wrote on Twitter: "Donald, don't be self-indulgent. Mexico has spoken, we will never ever pay for the #F******Wall."
Mr Trump, whose campaign rallies were filled with supporters chanting "build the wall", signed the documents giving it the go-ahead on Wednesday - just as a Mexican delegation led by foreign minister Luis Videgaray arrived at the White House for talks.
The US president said: "Beginning today, the United States of America gets back control of its borders."
Meanwhile, the head of the agency in charge of securing US borders with Mexico and Canada has left the organisation.
Border Patrol chief Mark Morgan was asked to step down as the agency moves towards tougher immigration laws, an official said.
Also, a number of senior career diplomats are leaving the State Department.
None of the departures has been linked directly to the Trump presidency - but many diplomats have expressed private concerns about serving in the administration.