Of the 245 prisoners of the opposition that Nicaragua was holding, 222 have been freed.

The deported prisoners were Daniel Ortega detractors who were released from prison.

The Nicaraguan government reportedly made the decision "unilaterally," which was welcomed by the US State Department.

Opposition politicians who intended to challenge Ortega in the 2021 election but were imprisoned in the lead-up are among those freed.

With his most ardent rivals behind bars, Ortega won the election for a fourth time in a row. He has held the position of power continuously since 2007.

US President Joe Biden said in an interview for the US Spanish-language network Telemundo that he was unsure whether this indicated that Nicaragua was prepared to change its approaches to human rights but added: "We're happy to receive them and I'm glad they're out."

On local television, Ortega claimed that the freed inmates were "agents" of foreign governments who aimed to undermine national sovereignty. According to the Reuters news agency, he said, "Let them have their mercenaries."

According to sources in the opposition in Nicaragua, those who were set free had their nationality taken away, and a representative of the judiciary described them as "traitors" who had been deported.

Opposition leader Juan Sebastian Chamorro and former presidential candidate Felix Maradiaga were among the prisoners freed. Maradiaga claimed he learned he had lost his citizenship soon after arriving in the US.

"I will always identify as a Nicaraguan. I will always be in love with Nicaragua, not just because it is where I was born, but also because it is a place where I hope to see democracy "He informed the press.

The Biden administration had been putting pressure on the Nicaraguan government to free the detainees, referring to the 2021 election there as "a pantomime." The US claimed that their detention was arbitrary.

Their charter flight to Dulles airport, close to Washington, DC, was arranged with assistance from the US, according to the US state department.

"Some of these individuals have spent years in prison, many of them for exercising their fundamental freedoms, in awful conditions and with no access to due process," it said in a statement.

Other members of the influential Chamorro family, which has long opposed the government of President Ortega, were among those released.

Juan Sebastian Chamorro's cousin Cristiana, whose mother Violeta defeated Daniel Ortega in the 1990 election, was one of those who had planned to stand against Mr Ortega in the 2021 polls.

She was seen by many in the opposition as their best hope of defeating Mr Ortega.

But shortly after she announced she would run for president, prosecutors accused her of money laundering. She was subsequently sentenced to eight years in prison.

She was deported along with her brother, Pedro Joaquín Chamorro, who was also sentenced last year.

A student opposition umbrella group, Nicaraguan University Alliance, said two of its members, Lesther Alemán and Max Jerez, were also on board the plane headed to the US.

Students were at the forefront of anti-government protests which rocked Nicaragua in 2018 and the two student leaders remained vocal critics of the government led by President Ortega and his wife, Vice-President Rosario Murillo, until their arrest in 2021.

Members of the Nicaraguan University Alliance said they would continue to fight for the rights of those sent to the US so that they "can return from exile and exercise their rights fully".