“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,” the official, who spoke on condition of anonymity, said in a statement on Thursday.
The Nicaraguan government did not immediately confirm the release.
The New York Times reported that the US government sent a plane to the Nicaraguan capital of Managua to fly the freed prisoners to Washington, DC. The flight is expected to arrive about noon local time (17:00 GMT).
Ortega has maintained that his imprisoned opponents and others were behind the 2018 protests that he said were part of a plot to overthrow him.
Tens of thousands of people have fled into exile, most notably to neighbouring Costa Rica, since Nicaraguan security forces cracked down on those anti-government demonstrations.
More recently, the US and European Union have accused Ortega of launching a new campaign of unjustified arrests in the lead-up to 2021 elections, as dozens of opposition leaders and presidential hopefuls were detained.
US President Joe Biden’s administration denounced the vote, which saw Ortega win a fourth consecutive term, as a “sham” – and Washington and its allies have heaped new sanctions on the government in Managua.
Many of those arrested have been sentenced to lengthy prison terms, often on charges of “conspiracy to undermine national integrity”.
In June of last year, United Nations then-human rights chief Michelle Bachelet said the situation in Nicaragua was deteriorating amid arbitrary detentions, harsh prison conditions, a lack of due process, increased state control over academic institutions and non-profit organisations, and curbs to freedom of association.
“I strongly urge the government of Nicaragua to uphold – not move further away from – its human rights obligations. I call on authorities to immediately cease policies which are today only serving to isolate the country and its people from the regional and international communities,” she said.
On Thursday, the senior Biden administration official said the US facilitated the transportation of the freed individuals to the country, where they will be paroled for humanitarian reasons into the country for a period of two years.
The official said the US government considered the mass release a positive step by Nicaragua, adding that all of those who left the Central American country did so voluntarily and are to receive medical and legal assistance upon arrival in the US.
‘Hallelujah’
A Nicaraguan judge later read out a statement saying that the 222 prisoners had been “deported”.
Octavio Rothschuh, a magistrate on the Managua Appeals court, said the operation was carried out under an order issued on Wednesday that declared the prisoners “traitors to the country”. He said they were deported for actions that undermined Nicaragua’s independence and sovereignty.
Later in the day, Nicaragua’s Congress unanimously approved a constitutional change allowing “traitors” to be stripped of their nationality. It will require a second vote in the next legislative session later this year.
Meanwhile, Arturo McFields, the former Nicaraguan envoy to the Organization of American States, who resigned from his post last year over the Ortega government’s human rights record, welcomed the release of the prisoners as “excellent” news.
“Hallelujah, glory to God,” McFields said in a video posted on Twitter.
Family members of some of those released confirmed that their loved ones were flying to Washington, DC.
Berta Valle, the wife of opposition leader Felix Maradiaga, said the US Department of State told her that her husband was on the plane, as reported by The Associated Press news agency.
Georgiana Aguirre-Sacasa, the daughter of Nicaragua’s former foreign minister Francisco Aguirre-Sacasa, also told The Guardian newspaper that her father was among those freed.
“This is huge,” she said. “This has been a very long slog for us and I just can’t believe it.”
It was not immediately clear which other prisoners were released.