Last month, European Union officials signed a deal with Sudan to improve counterterrorism cooperation, again with a view toward lifting sanctions.
In January, protests erupted in Sudan after the government put forward a new budget that would have cut economic subsidies, possibly leading to higher consumer prices, while continuing to pour resources into military spending. The protests, fueled in part by the opposition Communist Party, led to the arrests of the political prisoners.
Last year, Mr. Bashir named a longtime ally to the new post of prime minister and said he would not seek re-election. But that is a pledge he has made and reneged on in the past.
“He’s a big liar, and I don’t think he will hand over power,” said Jalal Moustafa, an activist with the opposition Sudanese Congress Party, who says he was jailed from Jan. 6 to 15 without charges — the sixth time he has been held by the authorities.
“I was detained as a pre-emptive action to avoid us talking to people so they could cordon off the streets,” Mr. Mustafa, 58, said in a phone interview. He said he was verbally but not physically abused.
Mr. Bashir freed some 80 political prisoners in late February but at least 50 others remained in detention as of last weekend, including Mohamed Mokhtar al-Khatib, the leader of Sudan’s Communist Party.
Mr. Mustafa suggested that Mr. Bashir had freed the prisoners in anticipation of a scheduled visit by United Nations human rights officials.
Jehanne Henry, a Human Rights Watch researcher who closely monitors Sudan, said that among those freed were Amjed Farid, a human-rights activist; Salih Mahmoud Osman, a human rights lawyer; Mohieldeen Aljalad, a communist activist; and Dr. Sidiq Kaballo, an economist.
“We know that at least a dozen are over 70, and another dozen over 60, and many of these older guys do have various health conditions,” she said of the other prisoners. The oldest was 83, she said.
“We have yet to receive reports of beatings and torture, but these are common in Sudan’s national security detention facilities,” she added. “They are notorious for keeping people in very cold rooms with lights on constantly and subjecting them to beatings during interrogation, and we have documented those patterns for years.”