Former US President Donald Trump has blasted his successor Joe Biden for “obsessing over how to protect Ukraine’s border,” while accusing his government of turning a blind eye to the crisis at the America's own frontier with Mexico.

“Everyone in Washington is obsessing over how to protect Ukraine’s border, but the most important border in the world right now for us is not Ukraine’s border, it’s America’s border,” Trump told his supporters at a “Save America” rally in Conroe, Texas on Saturday.

Citing record-high numbers of illegal migrants reaching the US-Mexico border, the ex-president likened the influx of people to an “invasion” threatening US security. He went on to argue that Biden had already “surrendered” the US border, and “now the entire planet is intruding across it as though America has been defeated on the field of battle.”

“Before our leaders talk about invasions of other countries they need to stop the invasion of this country,” Trump added, suggesting that the US should ramp up troops at its southern border instead of deploying American soldiers closer to Russia’s doorstep.

"Before Joe Biden sends any troops to defend a border in Europe, he should be sending troops to defend our border right here in Texas"

Trump spoke at the rally just a day after Biden told the media that American troops would be sent to Eastern Europe “in the near term.” Earlier this week, the Pentagon had put some 8,500 troops on “heightened alert” with a view to dispatching them to region.

While the Pentagon ruled out the possibility of US military involvement in “combat operations” in Ukraine, top US generals painted a grim picture of the aftermath of a potential full-blown conflict between Kiev and Moscow, warning of “horrific” consequences and “significant casualties,” even though Russia has consistently denied it’s planning to invade its neighbor.

Ukrainian President Volodymyr Zelensky also sought to dismiss reports of an “imminent” invasion of Ukraine by Russia, pleading with Western media and politicians to stop causing unnecessary panic.