BAGHDAD, Nov 24 (Reuters) - Basra's airport and port will close on Friday in protest after car bombs in a Shi'ite stronghold of Baghdad killed 160 people, an official in the southern Iraqi city said. It was not clear how long the closure would last. Authorities imposed a curfew in Baghdad after the bombings, the largest single attack of the war, fearing sectarian reprisals. Iraq's transport ministry is controlled by the political faction of Shi'ite cleric Moqtada al-Sadr, whose Baghdad stronghold was hit by the car bombs on Thursday. Iraq depends almost entirely on its southern oil export terminals since sabotage attacks have made a northern oil pipeline unusable for most of the last three and a half years.