Havana, Cuba (CNN) -- Another four Cuban political prisoners are expected to leave Havana for Madrid, Spain, no later than Wednesday, the head of Cuba's independent Commission on Human Rights and National Reconciliation told CNN.
"It depends on the space available on the flights," Elizardo Sanchez said Tuesday in a telephone interview. "But some will leave tonight; the rest (of the four prisoners) by Wednesday."
The four Cuban prisoners are part of a group of 20 expected to leave for Spain in the coming days, Cuba's Roman Catholic Church announced Monday.
After seven other dissidents arrived Tuesday from Cuba, a Spanish Foreign Ministry spokesman said three more dissidents were expected to arrive Wednesday and a fourth on Thursday -- all of them aboard commercial flights from Havana.
The four in this latest group were expected to be accompanied by relatives, as were the seven who arrived Tuesday, the spokesman said.
CNN's Al Goodman contributed to this story from Madrid
