Donald Trump has vowed to cut financial aid to a number of Central American countries while also declaring a national emergency in light of the caravan of migrants making its way to the US border.

“Sadly, it looks like Mexico’s Police and Military are unable to stop the Caravan heading to the Southern Border,” he wrote after Mexican riot police failed to contain thousands of people from crossing into the country.

The caravan, mostly Hondurans, crowded into the Mexican border city of Tapachula over the weekend after trekking on foot from the Guatemalan border. Organisers claim there are now more than 7,000 people in it, which will take about a week to reach the US border.

President Trump has repeatedly called for immigration law reform in light of the influx of undocumented immigrants fleeing rampant gang violence and poverty in Honduras, Guatemala, and El Salvador. He has made the issue – and his hardline stance – central to the upcoming midterm elections in Congress.

“I have alerted Border Patrol and Military that this is a National Emergy [sic]. Must change laws!” Mr Trump said. “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.

“Criminals and unknown Middle Easterners are mixed in,” the president wrote. He has repeatedly called the thousands on the Mexico border “criminals”.

He has been speaking about the issue of immigration at dozens of political rallies across the country ahead of the 6 November midterm elections. He is due to hold another “Make America Great Again” rally in Texas on Monday night.

“Every time you see a Caravan, or people illegally coming, or attempting to come, into our Country illegally, think of and blame the Democrats for not giving us the votes to change our pathetic Immigration Laws!,” Mr Trump said, as a reminder his supporter base.

Melania Trump: ‘I really don’t care’ jacket was message for media, not separated migrant children

The sentiments are echoed in his now infamous campaign rally line: “Democrats create mobs, we create jobs”.

The president also restated his threat to cut off foreign aid to Guatemala, Honduras, and El Salvador, much of which is aimed at violence prevention and poverty reduction.

According to the US Agency for International Development (USAID) in 2016, the US gave Honduras nearly $128m, Guatemala $297m, and El Salvador $75m in aid across all federal agencies mostly aimed towards counter-narcotics activities, military training, agricultural subsidies, and violence prevention.

By next year, those sums were projected to fall to $69.4m for Guatemala, $65.8m for Honduras, and $45.7m in the case of El Salvador.

Undocumented immigration across the US-Mexico border Show all 14 1 /14 Undocumented immigration across the US-Mexico border Undocumented immigration across the US-Mexico border Immigrant children, many of whom are separated form their parents, are housed in Texas' tent city Reuters Undocumented immigration across the US-Mexico border A two-year-old Honduran asylum seeker cries as her mother is searched and detained near the US-Mexico border Getty Undocumented immigration across the US-Mexico border Undocumented migrants ride on the top of a freight train referred to as the beast, or La Bestia Getty Undocumented immigration across the US-Mexico border A cage inside a US Customs and Border Protection detention facility in Texas Reuters Undocumented immigration across the US-Mexico border US Border Patrol Academy All new agents must complete a months-long training course at the New Mexico facility before assuming their posts at Border Patrol stations, mostly along the US-Mexico border Getty Undocumented immigration across the US-Mexico border US-Mexico border fence A group of young men walk along the Mexican side of the US-Mexico border fence in a remote area of the Sonoran Desert Getty Undocumented immigration across the US-Mexico border US-Mexico border fence in the US Man looks through US-Mexico border fence into the US in Tijuana, Mexico Getty Undocumented immigration across the US-Mexico border US-Mexico border fence US Border Patrol agent Sal De Leon stands near a section of the US-Mexico border fence while stopping on patrol on in La Joya, Texas Getty Undocumented immigration across the US-Mexico border US Border Patrol Academy US Border Patrol instructor yells at trainees after their initial arrival to the academy Getty Undocumented immigration across the US-Mexico border Memorial service in Guatemala Families attend a memorial service for two boys who were kidnapped and killed in San Juan Sacatepequez, Guatemala. Crime drives emigration from Guatemala to the United States, as families seek refuge from the danger Getty Undocumented immigration across the US-Mexico border Arrests on the border Undocumented immigrants comfort each other after being caught by Border Patrol agents near the US-Mexico border Getty Undocumented immigration across the US-Mexico border Detention holding facility A boy from Honduras watches a movie at a detention facility run by the US Border Patrol Getty Undocumented immigration across the US-Mexico border Mexican farm workers Mexican migrant workers harvest organic parsley at Grant Family Farms in Wellington, Colorado Getty Undocumented immigration across the US-Mexico border Mexican family in Arizona A Mexican immigrant family sits in the living room of their rented home in Tuscon, Arizona. The family that Arizona's new tough immigrant law had created a climate of fear in the immigrant community. Getty

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.

Mexican officials also issued their own warning to the caravan, stating only those who met the country’s standards for refugee status would be allowed to enter at its southern border but to no avail.

Several people rushed a bridge gate at the border between Guatemala and Mexico or crossed the Suchiate River to enter. As crowds persisted, Mexican police did allow women and children to enter and seek refuge.

Support free-thinking journalism and attend Independent events

A similar caravan of approximately 1,500 people made its approach in April, just weeks before the Trump administration began its family separation policy and putting National Guard troops along the 2,000-mile US-Mexico border.

The separation policy stemmed from a zero-tolerance approach to illegal immigration where all adults face prosecution, even if it means removing them from infants travelling with them.

Several of those who had crossed without documentation were seeking asylum, which requires physical entry into the US before an application for the protected status can be considered per American immigration laws.