Former Georgia congresswoman Cynthia McKinney revealed in a phone call posted online that she is in an Israeli prison with others who attempted to run a blockade to deliver supplies to Gaza.

McKinney and about 18 other activists in Israeli custody for the past three days will likely be released by Sunday, according to the Israeli embassy in Washington, D.C.

Spokesman Jonathan Peled said preparations are being made to deport the activists. "It is taking slightly longer. Former congresswoman McKinney is not cooperating with the authorities" and refusing to sign a document acknowledging deportation, he said.

"It'll take a couple more days before she is put on a plane and flown out of Israel," Peled said.

A blog entry Thursday on a MySpace page for McKinney said the passengers refused to admit in writing to violating the blockade and trespassing Israeli territorial waters.

The Greek-registered Arion with 21 passengers aboard was in the Mediterranean Sea about 23 miles off the Gaza coast when it was intercepted Tuesday. Israel has blockaded entry to Gaza, which is governed by the organization Hamas, for two years.

The Free Gaza Movement, which organized the voyage, contends the ship was carrying humanitarian aid.

The organization, which has made more than a half dozen sailings to deliver aid to Gaza since August 2008, had renamed the ship Spirit of Humanity and refers to it by that name.

The Israelis rerouted the ship to the port of Ashdod after the seizure. Two of the passengers who signed the waivers have been released from custody and deported, Peled said.

New York journalist Don DeBar said McKinney called him early Thursday. DeBar covered McKinney's campaign last year as the Green Party presidential candidate and they stayed in touch.

"She sounded okay," DeBar said.

McKinney said in the online interview (listen to the interview here here ) that she was in a prison cell block with women from different countries detained for arriving in Gaza.

"We have not committed any crime, we have been detained," McKinney said. We want the people of the world to see how we have been treated just because we wanted to deliver humanitarian assistance to the people of Gaza."

McKinney called on President Barack Obama to press Israel to assist the Palestinian people.

Among the activists on the ship were McKinney, who twice represented Georgia in the U.S. House of Representatives; and Mairead Maguire, the 1977 recipient of the Nobel Peace Prize for co-founding a group that worked for peace in Northern Ireland.

In a statement, Irish Foreign Minister Micheál Martin called for the immediate release of Maguire and another Irish citizen also being detained.

McKinney's father said he spoke briefly with her on Thursday and that she told him she was all right.

"We didn't have a conversation. She just said she was all right, and that was about it," Billy McKinney of Atlanta said.

The former Georgia legislator and political figure admitted he was worried despite his daughter's assurances.

"I'm always worried about her," he said. "I'm a father. I'm a parent. I'm always worried."