Delcy Rodriguez has been sworn in as Venezuela's interim president in a parliamentary session that began with demands for the release from US custody of ousted leader Nicolas Maduro.


Rodriguez, 56, vice president since 2018, said she was pained by what she called the kidnapping of Maduro and his wife Cilia Flores who were seized by US forces in an overnight raid on Saturday.


In dramatic scenes inside a New York court room two hours earlier, Maduro insisted he was still the president of Venezuela as he pleaded not guilty to four charges of drug trafficking and terrorism.


Meanwhile the US faced sharp criticism at the UN, but the US ambassador said the largest energy reserves in the world could not be left in the hands of an illegitimate leader, a fugitive from justice.


Before the court appearance, the UN Security Council held an emergency session to discuss the situation in Venezuela.


The ambassador for Venezuela, Samuel Moncada, said his country had been the target of an illegitimate armed attack lacking any legal justification.


The US ambassador to the UN, Mike Waltz, justified the attack by describing Maduro as an illegitimate so-called president.


Waltz added that the US had carried out a surgical law enforcement operation to apprehend Maduro, whom he is also referred to as a fugitive from justice.


Maduro has been accused of narco-terrorism conspiracy, cocaine importation conspiracy, possession of machine guns and destructive devices and conspiracy to possess machine guns and destructive devices.


During Monday afternoon's court appearance, a member of the public began to yell in Spanish at Maduro that he would pay for what he had done.


Maduro turned to him and replied that he was a kidnapped president and a prisoner of war before being escorted out in shackles behind his wife through the back court door.


I'm a decent man. I am still president of my country, Maduro said earlier during the 30-minute hearing. Judge Alvin Hellerstein, 92, interjected to tell Maduro that there would be a time and a place to get into all of this.


Speaking just hours after Saturday's attack - which saw over 150 aircraft and 200 US personnel enter Venezuela - Trump had vowed the US would run Venezuela until a safe and proper and judicious transition was possible.


He also promised US oil companies would move into the country to fix infrastructure and start making money for the country.


Thousands of Venezuelans gathered outside the Federal Legislative Palace to show support for Maduro, his wife, and the interim president Rodriguez as she was sworn in.


Rodriguez indicated her government would engage in some cooperation with the US, saying: We invite the US government to collaborate with us on an agenda of cooperation oriented towards shared development within the framework of international law.


The next court hearing in Maduro's case has been scheduled for 17 March.