A move by Iran's central bank to lessen the role of the Revolutionary Guards and other military groups in the economy may be part of a wider power struggle.

Iran’s Central Bank (CBI) has announced plans to merge five military-linked banks with the state-owned Bank Sebah.

The move has the dual role of shoring up the ailing banking sector and also reducing the economic role played by Iran’s politically powerful armed forces.

President Hassan Rohani has sought to tackle this...