By Makini Brice and Delphine Schrank
WASHINGTON/TAPACHULA, Mexico (Reuters) - President Donald Trump on Monday vowed to begin curtailing tens of millions of dollars in aid to three Central American nations and called a caravan of migrants bound for the United States a national emergency as he sought to boost his party's chances in Nov. 6 congressional elections.
"Guatemala, Honduras and El Salvador were not able to do the job of stopping people from leaving their country and coming illegally to the U.S. We will now begin cutting off, or substantially reducing, the massive foreign aid routinely given to them," Trump wrote in a series of Twitter posts.
Trump and his fellow Republicans have sought to elevate the caravan, which has made its way into Mexico bound for the U.S. border, and immigration as campaign issues ahead of the midterm elections, in which his party is fighting to maintain control of the U.S. Senate and House of Representatives.
"Remember the Midterms!" Trump wrote in Twitter posts decrying the caravan and attacking Democrats on immigration, as Republicans sought to energize their conservative political base.
Trump, who has taken a hard line toward illegal immigration since taking office last year, also wrote that he had alerted the U.S. military and Border Patrol "that this is a National Emergy," though he did not say what actions he was planning. He also complained that Mexico's police and military "are unable to stop" the caravan.
U.N. spokesman Farhan Haq said it is estimated that the caravan includes more than 7,000 people, "many of whom intend to continue the march north" toward the United States.
At least 5,000 migrants, mostly Honduran, massed late on Sunday in the Mexican city of Tapachula near the Guatemalan border, local police said. About another 1,000 migrants were walking toward them from Ciudad Hidalgo further south, according to a Reuters witness.
In campaigning for Republican candidates last week, Trump highlighted the caravan issue. Trump travels to Texas, a key border state, later on Monday to campaign for Republican U.S. Senator Ted Cruz, who is seeking re-election.
Since Trump became president last year, the United States has already moved to sharply decrease aid to Central America.
In 2016, the United States provided some $131.2 million in aid to Guatemala, $98.3 million to Honduras, and $67.9 million to El Salvador, according to U.S. data. By next year, those sums were projected to fall to $69.4 million for Guatemala, $65.8 million for Honduras and $45.7 million for El Salvador. The cuts amount to a reduction of almost 40 percent for the three nations.
Trump was not specific about further aid cuts. Trump also said, without providing evidence, that "Criminals and unknown Middle Easterners" are mixed in with the caravan, a claim immigration advocates disputed.
Haq said U.N. Secretary-General Antonio Guterres spoke with the presidents of Honduras and Guatemala over the weekend and that an "emergency team" of personnel representing the United Nations High Commissioner for Refugees (UNHCR) had been sent to southern Mexico.
Immigration advocacy groups said cutting U.S. aid would be counterproductive to the goal of stemming a flow of migrants, noting that a key purpose of the assistance over the years has been to stabilize countries to make people less apt to leave.
Writing in response to Trump on Twitter, Democratic U.S. Representative Don Beyer said: "Trump and the Republicans have controlled the White House and Congress for the past two years. Anytime he whines about immigration, just remember that they have no real solutions."
Seeking to escape violence and poverty in their home countries, the migrants - men, women and children - have defied threats by Trump that he will close the U.S.-Mexico border if they advanced, as well as warnings from the Mexican government.
Most of the migrants were expected to stay in Tapachula through Monday, according to Mexican police at the scene. Police in riot gear shadowed the caravan's arrival along a southern highway but did not impede the migrants' journey.
The caravan was still a long way - more than 1,100 miles (1,800 km) - from the U.S. border. Long before it reaches the U.S. border, Mexico hopes to disperse the convoy using bureaucratic procedures, telling migrants to register with authorities in order to submit applications for asylum in Mexico.
That process can last weeks, and migrants are supposed to stay where they register while applications are processed. If they violate those rules, they face deportation.
Army Lieutenant Colonel Jamie Davis, a Pentagon spokesman, said that while National Guard troops are currently supporting the Department of Homeland Security on the border, the Pentagon had not been asked to provide additional support. There are currently 2,100 National Guard troops along the border in Texas, New Mexico, Arizona and California, according to the Pentagon.
White House and Border Patrol representatives did not immediately reply to requests for comment.
Congress has not fully funded Trump's proposed wall along the U.S.-Mexican border, which he has argued is needed to combat illegal immigration.
(Reporting by Makini Brice and Delphine Schrank; additional reporting by Susan Heavey and Idrees Ali in Washington and Michelle Nichols at the United Nations; writing by Will Dunham; editing by Jonathan Oatis)