The Mexican president has insisted his country will not pay for the border wall
Donald Trump has threatened to cancel a meeting with Mexico's president over the country's refusal to pay for his border wall.
The pair are due to meet next week in Washington, but the US president suggested they should skip the talks.
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
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 and insisted the US neighbour would "100%" pay for it.
But in a televised message to his country, Mexican president Enrique Pena Nieto reasserted that Mexico would not pay a single peso towards it.
"I have said it time and again: Mexico will not pay for any wall," he said.
He did not mention the upcoming meeting in his address, but he has faced growing calls to scrap it himself.
Former Mexican president Vicente Fox, meanwhile, had more colourful language for Mr Trump on Twitter:
Mr Trump - whose campaign rallies were filled with supporters chanting "build the wall" - said as he signed orders on the controversial wall on Wednesday: "A nation without borders is not a nation.
"Beginning today, the United States of America gets back control of its borders."
He added: "We are going to get the bad ones out. The criminals and the drug dealers and gangs and gang members and cartel leaders. The day is over when they can stay in our country and wreak havoc."
Mr Trump would need to get approval from Congress for any new funding for the wall - with costs estimated at €6m (US$6.5m) per mile for a single-layer fence by the Government Accountability Office.
The total cost, nature and extent of the wall remain unclear. The President last year put the cost at "probably US$8bn (€7.5bn)", although other estimates are higher.
But former CNN correspondent, Gina London, told the Pat Kenny Show here on Newstalk that erecting the wall will be more complicated than Mr Trump thinks.
The move forms part of the newly inaugurated President's crackdown on immigration.
Mr Trump is expected to follow up with an order temporarily suspending the US refugee programme, ending arrivals from Syria, and refusing visas to people from a number of predominantly Muslim countries.