Deputy Minister of Petroleum Amir Hossein Zamaninia said here on Saturday that no part of the country's oil assets have been blocked abroad.
Talking to IRNA, Zamaninia reiterated that the only issue is the way of transferring money and the expenses of oil exports which should be performed through the banking system.
'So far several Asian and European companies have voiced their willingness to buy oil from Iran,' he added.
During the sanctions years, international oil companies which worked with Iran avoided paying their debts.
Following the implementation of the Joint Comprehensive Plan Of Action (JCPOA) between Iran and the P5+1 - the United States, France, Britain, Russia, China and Germany - in Vienna, Austria, on July 14, the foreign companies started paying back Iranian debts gradually.