In an interview with CBS News, Machado said the transitional government in Caracas under acting President Delcy Rodríguez is "starting to realise that things have changed for good".
Machado, who won the Nobel Peace Prize last year for her work in the Venezuelan opposition, attributed the recent changes under Rodríguez solely to pressure from the United States.
"If that pressure were taken away, she would turn around and go back to where her loyalty is," Machado said.
Since the US military operation on January 3 to oust president Nicolas Maduro, Venezuela has released hundreds of political prisoners under pressure from the US.
On Friday, the government announced a comprehensive amnesty for political prisoners from 1999 to the present day.
Many of those released so far were detained during protests against Maduro's re-election in 2024, which was overshadowed by allegations of fraud.
Rights activist Javier Tarazona was among those freed, legal rights group Foro Penal said on Sunday, in the latest high profile liberation in a weeks-long process that families of the detained say has moved too slowly.
Foro Penal says it has verified more than 300 liberations of political prisoners since the government announced the new series of releases on January 8.
It added on X on Sunday that several others had been released alongside Tarazona from the Helicoide.
Tarazona is the director of FundaRedes, which tracks alleged abuses by Colombian armed groups and the Venezuelan military along the countries' border.
He was arrested in July 2021, accused of terrorism and conspiracy.
"After 1675 days, four years and seven months, the day we've so wished for has arrived, my brother Javier Tarazona is free," Tarazona's brother Jose Rafael Tarazona said on X.
"The freedom of one is hope for all."
Government officials - who deny holding political prisoners and say those jailed have committed crimes - have given a much higher figure of releases, of more than 600, but have not been clear about the timeline and appear to be including releases from previous years.
The government has never provided an official list of how many prisoners will be released nor who they are.
with DPA
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