Rubinstein warned Sharon that it would be hard to defend in court the law that Sharon wants passed, when at the same time the state is granting official status to children whose parents are illegal foreign workers and neither of whom is an Israeli citizen.
Asked about the letter, the Justice Ministry spokesman replied: "The security establishment asked the Justice Ministry to examine the possibility of denying automatic citizenship in cases where one of the parents is not Israeli.
"This is in response to a request from security sources following the involvement in terrorist activities of Israeli citizens who are the children of a resident of the Palestinian Authority and an Israeli citizen (as in the case of the bombing of the Mazza restaurant in Haifa last year).
"Rubinstein sent the letter to Sharon last week. He asked the prime minister to override Poraz and determine the government's policy regarding all of the citizenship issues that the Interior Minister had raised in recent weeks. These issues include refusing to grant automatic citizenship according to the Law of Return to anyone who converts while living in Israel, whether the conversion takes place in an Orthodox, Conservative, or Reform ceremony."
Poraz has also indicated that he wants to grant official status to the children of illegal immigrants who have grown up in Israel, and to stop deporting foreign workers who have married an Israeli, had children here, and then been divorced.
Rubinstein said he opposes all the changes Poraz wants to initiate and called on Sharon to block them.