Selling a immovable property.

My brother is in Singapore with his family. He is having residential plots here in Erode. This property was registered both my brother and his wife name. Now there is an offer to purchase his property. But my brother cannot plan his trip with entire family now. He alone can plan his trip. Now how can we sale this property as because it was registered both husband and wife name. Is Power of atterny taken from indian high commission will be eligible to sale this property?