A plane carrying American pro-democracy campaigners and other activists left Egypt on Thursday after a travel ban was lifted, the U.S. State Department confirmed, a move that is likely to defuse the deepest row between Washington and Cairo in decades.

"They have left,'' a Cairo airport official earlier told Reuters, without giving details. A U.S. military plane had been sent to Egypt to take the seven Americans and eight foreign campaigners after they posted bail.

NBC News reported that a State Department official confirmed the group's departure and said they were "en route" to the U.S.

A statement from Secretary Ray LaHood, whose son is among the activists, read: "I'm pleased the court has lifted the travel ban and am looking forward to my son's arrival in the U.S. I'd like to thank everyone for their thoughts and prayers during this time."

The staff have been charged with operating without a license and using illegal foreign funds to foment unrest.

The reported end of the travel ban comes four days after an Egyptian court adjourned the trial of 16 Americans and 27 others -- a mixture of other foreigners and Egyptians -- until April 26. Of the 16 Americans charged in the case, seven had been banned from leaving Egypt, including Sam LaHood, Egypt director of the International Republican Institute (IRI) and the son of the U.S. transportation secretary.

In Washington, the IRI on Thursday welcomed news of Egypt's decision to lift travel bans imposed on its staff, but said it remained concerned about the situation "and the impact it will have on Egypt's ability to move forward with the democratic transition that so many Egyptians have sought."

Sen. John McCain, R-Ariz., who recently visited Egypt in the hope of resolving the stand-off, issued a statement on Thursday saying he was "pleased and relieved" that these individuals are now able to return home to their families.

"At the same time, we remain concerned about the fate of the many Egyptian employees who have worked for these NGOs and who remain in Egypt, where they are still subject to trial," he added. "We will continue to advocate for the rights of these Egyptian NGO workers, who have done no wrong."

Cairo court adjourns trial of NGO workers

Rights campaigners say the case is retaliation by Egypt's ruling generals against pro-democracy groups that have been among the army's harshest critics since it took power when Hosni Mubarak was overthrown a year ago.

The U.S. pro-democracy groups whose staff have been charged deny they have done anything illegal. They say the crackdown is an attempt by Egypt's military rulers to derail democracy.

The case has severely strained Cairo's relations with Washington, and U.S. officials have threatened to cut off $1.5 billion in aid to Egypt if the dispute is not resolved.

Egypt says the case is a judicial matter and all groups must heed Egyptian law.

Some Egyptian officials have linked the funding of civil society initiatives to a U.S. plot to undermine Egypt's sovereignty — accusations the United States and the civil society workers deny.

The crisis escalated on Dec. 29 when Egyptian authority swooped the offices of the IRI and the National Democratic Institute, confiscating documents and computers and cash on the premises.

The government and the ruling military council say the case was initiated by the judiciary and is out of their hands.

Reuters and msnbc.com staff contributed to this report.

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