Ali Shamhani, the General of the Iranian Supreme Council for National Security, said on Sunday that Iran would close its border gates if the Kurdistan Regional Government (KRG) declared independence.
“If the Kurdistan Region separates from Iraq, we will review all the agreements we made with them,” Shamhani said.
Shamhani emphasized that the split had no legal basis, and would only serve to spark security concerns for the region.
Iran has voiced its opposition to the referendum, saying that the poll would only lead to new problems.
The controversial referendum slated for Sept. 25, results of which will be non-binding, will see residents of the Kurdish region vote on whether or not to declare independence from Iraq.
Baghdad, however, rejects the planned poll, saying it will adversely affect the fight against Daesh, which still maintains a significant presence in northern Iraq.
The Iraqi government also believes that holding the poll would violate the terms of the country's 2005 constitution.
Turkey also rejects the planned referendum, saying the region’s stability depends on the maintenance of Iraq’s unity and territorial integrity.