Modig, 27, heads the youth wing of the Christian Democrats in Sweden, was released from the hospital shortly after the crash but remains in Havana, where he met with Swedish embassy officials on Thursday.
"He is in good shape," Katarina Axelsson, the foreign ministry's spokesperson, told AFP. "It remains unclear when he will be able to leave Cuba. Cuban authorities have said he must be available for the police investigation."
A car carrying four struck a tree in southeastern Cuba on Sunday, killing Cuban dissidents Oswaldo Paya and Harold Escalante and injuring Modig and Angel Carromero Barrios, a Spanish politician.