Gov. Doug Ducey said Monday that hedoes not support closing the U.S.-Mexico border, as President Donald Trump has repeatedly threatened to do in recent days.

"I've said a thousand times or more, Mexico is our No. 1 trading partner, times four," Ducey told reporters. "So, I want to see us continue to be able to trade."

Ducey, a Republican, said he believes "the border does need attention," but it's a "humanitarian crisis, and Congress needs to act."

He said the White House was aware of his stance.

Trump on Saturday and again on Monday posted on Twitter that "Mexico must use its very strong immigration laws to stop the many thousands of people trying to get into the USA" or else he would shut down the border.

He'd delivered a similar ultimatum when speaking to reporters on Friday, saying there was "a very good likelihood that I’ll be closing the border next week" if Mexico didn’t "get with it" in terms of blocking the flow of migrant families at the border.

His administration has released families from custody as processing centers struggle to handle the recent uptick.

Apprehensions at the southern border overall had hit historic lows in recent years. Agents caught fewer than 400,000 migrants in 2018, versus the more than 1 million a year detained annually through the 1990s and 2000s.

This story includes reporting from USA Today.

Reach the reporter at maria.polletta@arizonarepublic.com or 602-653-6807. Follow her on Twitter @mpolletta.

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