WASHINGTON/TAPACHULA, Mexico — US President Donald Trump on Monday vowed to begin curtailing millions of dollars in American 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 US. 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.

The caravan, an estimated 7,000 to 10,000 Central Americans who have cited violence and poverty in their homelands as their reasons for leaving, is in southern Mexico, inching toward the distant US border.

Trump and his fellow Republicans have sought to focus on the caravan and immigration ahead of the midterm elections, where his party is fighting to maintain control of the House and Senate.

“Remember the Midterms!” Trump tweeted.

Trump’s remarks also seemed aimed at piling pressure on Mexico to stop the caravan, something that he complained the Mexican police and military had failed to do.

Mexico, which has refused Trump’s demands that it pay for a border wall between the countries, tries to walk a fine line between showing solidarity with the Central American migrants and responding to Washington’s demands to control its borders.

The caravan was moving north again on Monday as migrants left the southern Mexican city of Tapachula near the Guatemalan border, bound for the town of Huixtla, also in Chiapas state.

Some shielded themselves from the midday sun with umbrellas, others with bits of cardboard on which they had slept the previous night. As they left the city and crossed a highway, Mexican drivers honked their horns in support.

US administrations have long seen aid programs as an essential part of efforts to stabilize the countries of Central America and stem the flow of migrants leaving.

But since Trump became president last year, the US already has moved to sharply decrease aid to the region.

In 2016, the United States provided some $131 million in aid to Guatemala, $98 million to Honduras, and $68 million to El Salvador, according to US data. By next year, those sums were projected to fall to $69 million for Guatemala, $66 million for Honduras and $46 million for El Salvador — a reduction of almost 40 percent for the three nations.

Later on Monday, Trump headed to Texas, a key border state, to campaign for Republican US Senator Ted Cruz.

REUTERS