Hundreds of protesters have gathered outside Downing Street and called for Venezuelan president Nicolas Maduro to be freed.
Demonstrators chanted “free Maduro” and listened to speeches from the likes of Jeremy Corbyn and Richard Burgon.
The MPs told Prime Minister Sir Keir Starmer to stand up to US President Donald Trump.
In the crowd, a small group of men stamped on a US flag before tearing it up.
The protest came as Foreign Secretary Yvette Cooper was making a statement to the Commons a short distance away.
The Prime Minister has come under pressure from MPs on Labour’s left to condemn the US military action that saw Maduro captured and taken to New York.
Among the international laws the US could be at risk of breaching, if it provides no justification for the attacks, is the founding charter of the United Nations.
Article 2 of the UN charter says all members should refrain from “the threat or use of force against the territorial integrity or political independence of any state”.
A defiant Maduro declared himself the “president of my country” as he protested against his capture and pleaded not guilty to the federal drug-trafficking charges on Monday.
The courtroom appearance, Maduro’s first since he and his wife were seized from their home, kickstarts the US government’s most consequential prosecution in decades of a foreign head of state.
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