Mahmud said: "We've not been officially told about the status of our leader. It's the right of any citizen to visit another. We hope the government will not breach that right."
Hasina was welcomed back on Monday by more than 20,000 Awami League supporters who defied a ban on demonstrations to greet her.
"The whole situation is not clear to us. We want to know what actually is the position of the government about the status of our leader," Mahmud said.
The movements of Hasina's rival, Khaleda Zia - the last Bangladesh prime minister and leader of the Bangladesh Nationalist Party (BNP) - had also been restricted since last month. She cannot leave her home without permission from security forces, her aides said.
The security forces also restrict who she can meet and turn back most visitors, they said.
However, the government has said it has placed no curbs on Zia's movements or her visitors.
Zia's BNP led a coalition government until last October, when it handed power to a caretaker administration ahead of January elections.
But the elections were scrapped and emergency rule imposed on January 11 by Iajuddin Ahmed, the president, after months of violent clashes between BNP and Awami League supporters.
The military-backed interim government took over and has pledged to hold elections by the end of 2008 after cleaning up Bangladesh's notoriously corrupt political system.