WASHINGTON (AP) - President Donald Trump is taking the shutdown battle to the U.S.-Mexico border, seeking to bolster his case for a border wall after the latest negotiations with Democrats blew up over his funding demands.

During his visit Thursday to McAllen, Texas, Trump plans to visit a border patrol station and a section of the border. McAllen is located in the Rio Grande Valley, the busiest part of the border for illegal border crossings.

Trump stalked out of a meeting with congressional leaders Wednesday as efforts to end the shutdown fell into deeper disarray. Hundreds of thousands of federal workers now face lost paychecks on Friday.

The unraveling talks prompted further speculation about whether Trump would declare a national emergency and try to authorize the wall on his own.

Meanwhile, Senate Majority Leader Mitch McConnell is blocking an attempt by Democrats to force a vote on legislation to reopen the federal government.

Democrats went to the Senate floor Thursday and asked for consent to vote on a series of bills that would end the partial government shutdown, which was in its 20th day.

Sen. Ben Cardin of Maryland said the bills were uncontroversial and were broadly supported by Republicans in the past. Cardin says the country is being "held hostage" by President Donald Trump as he seeks funding for a U.S.-Mexico border wall.

McConnell objected to the Democratic request, saying he won't agree to "pointless show votes" on bills Trump won't sign. McConnell noted that Democrats agreed in December to not vote on a funding package until a deal was reached by Trump and leaders from both parties.

The border wall was a signature campaign promise for Trump. Democrats have called a wall costly, ineffective and immoral.

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