US President Donald Trump urged Venezuela to free jailed opposition leader Leopoldo Lopez "immediately". The president posted a picture of himself and VicePresident Mike Pence with Lopez's wife at the White House.
"Venezuela should allow Leopoldo Lopez, a political prisoner & husband of @liliantintori (just met w/ @marcorubio) out of prison immediately," Trump tweeted, along with the photo, which also features Florida Senator Marco Rubio.
Lopez, the founder of Popular Will, one of the most hardline of the parties opposing Venezuelan President Nicolas Maduro, is serving a 14-year prison term on charges of inciting unrest at anti-government protests that left 43 people dead in 2014.
The meeting with Tintori was sure to enrage Maduro, who is already fuming over sanctions slapped on his powerful Vice President Tareck El Aissami, whom US authorities accuse of being involved in drug trafficking.
The drug allegations against El Aissami had already raised tensions between Washington and Caracas, which had so far been cautious in its stance towards Trump's new administration.
Maduro on Tuesday demanded the United States apologize for the sanctions and vowed to respond "forcefully." Shortly before Trump sent the tweet about Lopez, Maduro had warned the US leader that he would respond with a firm hand to any action by Washington he deemed to be aggressive.
"If they attack us, we will not be silent. Venezuela will respond firmly. Those who tangle with us will get an appropriate response," Maduro said on state television. Maduro added that he did not want any "problem with Mr Trump."
On Wednesday, Venezuela pulled CNN's Spanish-language television channel off the air, accusing it of spreading "propaganda" about an alleged visa racket at the country's embassy in Iraq.