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Venezuela’s attorney general has called for opposition leader Juan Guaidó to be banned from leaving the country and for his bank accounts to be frozen.
The move comes amid an escalating power struggle, after Mr Guaidó declared himself interim president last week.
He has been backed by the US and other countries. President Nicolás Maduro has major allies too including Russia.
Venezuela has been facing acute economic problems and there has been an upsurge in violence in recent weeks.
Protests have been held across the country since Mr Maduro began his second term on 10 January. He was elected last year during a controversial vote in which many opposition candidates were barred from running, or jailed.
At least 40 people are believed to have died and hundreds have been arrested since 21 January, the UN says.
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Hyperinflation and shortages of essentials such as food and medicine have forced millions to flee the nation.
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What did the attorney general say?
On Tuesday Attorney General Tarek William Saab asked the Supreme Court to take “precautionary measures” to prevent Mr Guaidó from fleeing the country or moving assets.
Mr Saab’s office said: “There have violence incidents in the country, statements by foreign governments and freezing of the assets of the Republic, which implies the commission of serious crimes that attack the constitutional order.”
The Supreme Court, which is loyal to Mr Maduro, is widely expected to back the move.
It comes shortly after the US said it had handed control of Venezuela’s US bank accounts to Guaidó, whom it now regards as the country’s legitimate president.
US National Security Adviser John Bolton responded with a tweet calling Mr Saab the “former Venezuelan Attorney General” and warning of “serious consequences for those who attempt to subvert democracy and harm Guaido”.
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On what does Guaidó base his claim to the presidency?
He says the constitution allows him, as the head of the National Assembly, to assume power temporarily when the president is deemed illegitimate.
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“My duty is to call for free elections because there is an abuse of power and we live in a dictatorship,” Mr Guaidó told the BBC on Monday.
He added: “In Venezuela, we either accept domination, total oppression and torture… from Maduro’s regime, or we choose freedom, democracy and prosperity for our people.”
Mr Guaidó said the Maduro administration was “killing young poor people” in the streets.
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What action is the US taking?
On Monday Mr Bolton announced sanctions against Venezuela’s state-owned oil firm PDVSA to ensure that President Maduro could “no longer loot the assets of the Venezuelan people”.
He also hinted at possible military action, reiterating that “all options are on the table”.
Mr Bolton appeared at a news briefing with a notepad containing the words “5,000 troops to Colombia”, which borders Venezuela.
On Tuesday acting US Defence Secretary Patrick Shanahan declined to say whether the Pentagon was considering sending troops. “I haven’t discussed that with Secretary Bolton,” he told reporters.
Also on Tuesday the state department issued a travel advisory urging US nationals not to go to Venezuela because of “civil unrest, poor health infrastructure, and arbitrary arrest and detention of US citizens”.
What about other countries?
More than 20 nations have followed the US in recognising Mr Guaidó as interim president. Many EU members have called for new elections.
But other powers including Russia, China, Mexico and Turkey have publicly backed Mr Maduro.
On Tuesday Russian Foreign Minister Sergei Lavrov said the US sanctions violated “all possible international norms” and “pledged to do everything to support the legitimate government of President Maduro”.