Venezuela has held nationwide armed forces exercises and the crisis-hit government is calling on civilians to join reserve units to defend against a possible attack after US President Donald Trump warned that a "military option" is on the table.
Mr Trump made the threat two weeks ago and on Friday he signed an order prohibiting dealings in new debt from the Venezuelan government or its oil company, a move to hobble financing that Trump says is fuelling socialist President Nicolas Maduro's "dictatorship."
"Against the belligerent threats of the United States, all Venezuelans between the ages of 18 and 60 are required to contribute to the integral defence of the nation," said an announcement broadcast early on Saturday on state television.
Mr Maduro used Mr Trump's threat to try to energise his political base, broadcasting images of rifle-carrying civilians negotiating obstacle courses and learning hand-to-hand combat.
The government created the hashtag #EsHoraDeDefenderLaPatria, which translates as "It's Time To Defend The Homeland," to promote the exercises.
TV images showed Venezuelans young and old entering military reserve registration centres.
However, there was no evidence that registration reached far beyond government employees and Mr Maduro's Socialist Party loyalists.
Scenes were aired of camouflaged sharp-shooters firing their weapons while military commanders gave fiery speeches at "anti-imperialist" rallies. More exercises were scheduled for Sunday.
Opposition figure and former presidential candidate Henrique Capriles sent a tweet dismissing the weekend training program as an expensive farce.
He said Mr Maduro should focus instead on bringing down Venezuela's high crime rate.