Trump: Mexico 'has taken advantage of the US for long enough'

President Donald Trump continued railing against Mexico on Friday amid heightening tensions over the wall he wants to build on the southern border of the US.

"Mexico has taken advantage of the US for long enough," Trump tweeted Friday morning. "Massive trade deficits & little help on the very weak border must change, NOW!"

Mexico President Enrique Pena Nieto canceled a planned meeting with Trump after Trump tweeted = Thursday morning, "If Mexico is unwilling to pay for the badly needed wall, then it would be better to cancel the upcoming meeting." Nieto had released a statement on Wednesday saying Mexico "will not pay for any wall."

Trump has repeatedly insisted that Mexico will reimburse the US for the border wall.

Trump adviser Kellyanne Conway told Fox News on Friday that the relationship between Mexico and the US has "not imploded."

"This one meeting has been canceled and that was a mutual cancellation," she said.

White House press secretary Sean Spicer told reporters on Thursday that the administration is pushing for a 20% border tax on Mexican imports to help pay for the wall.

"When you look at the plan that's taking shape now, using comprehensive tax reform as a means to tax imports from countries that we have a trade deficit from, like Mexico," he said.

Republicans have estimated the wall would cost between $12 billion and $15 billion.

Bob Bryan contributed to this report.