US President Donald Trump attends a working session at the G-20 summit in Hamburg, northern Germany, Saturday, July 8, 2017. Photo: Reuters / Markus Schreiber, Pool.

US President Donald Trump on Tuesday vowed to go around Congress and utilize the US military to build a wall along the US-Mexico border if he does not get funding, just hours before he is to meet with the top two Democratic lawmakers.

In a series of early-morning tweets, Trump praised his administration’s moves to block migrants at the US border with Mexico and said efforts to stop a caravan of migrants seeking to reach the United States were a success, and vowed that “the Wall will get built.”

The president has made funding for the border wall, a campaign promise, a central issue as Congress seeks to finalize spending before some federal government funding expires on Dec. 21.

Trump is scheduled to meet at the White House later Tuesday with US Senate Democratic Leader Chuck Schumer and House Democratic Leader Nancy Pelosi, who is seeking to become House Speaker when her party gains control of the chamber next month.

“If the Democrats do not give us the votes to secure our Country, the Military will build the remaining sections of the Wall,” Trump said on Twitter ahead of the 11:30 a.m. EST meeting.

Trump deployed the US military to the border area before November congressional elections, calling the caravan an “invasion,” and critics decried the action as politically motivated. He has continued to press immigration issues in what could be a political standoff that could shutter the US government.

The president wants $5 billion this year to pay for the border wall in addition to other funds for separate border security measures. Democrats, who have fiercely opposed the wall, say they would back the $1.6 billion that Senate Republicans have sought for the fiscal year to pay for related technology.

During the 2016 presidential campaign, Trump promised that Mexico would pay for the wall, but turned to Congress after Mexico refused.