In a statement posted on the Pastebin.com, a group calling themselves the "Israel Defence Force Team" said they had hacked the Iranian sites in response to similar attacks on an Israeli newspaper and hospital website a day earlier.

"If the Arab hackers thought that the attack on the Israeli websites will pass in silence, I have to said all Arab hackers: You have a mistake," a statement in broken English said.

The group said they would take down Iran's ministry of health website, along with the website of the Iranian channel Press TV.

"Also there are other Iranian sites were hacked just for fun at the following addresses: http://www.sarallahco.ir, http://shiadesign.ir, http://syakh.ir," the statement said.

"Ahmadinejad what do you have to say about that??" it added, in reference to Iranian President Mahmoud Ahmadinejad.

The statement said the attacks would begin at 4:30 pm (1960 IST).

The hacked sites appeared to have their home pages blacked out, showing only a photograph of an Israeli flag and text reading "HACKED BY Israel Defence Force Team".

"We love Israel. Hi Arabs, you have been hacked by IDF Team," the text continued.

Iranians are not ethnically part of the Arab nation.

The attacks were the latest salvo in a cyberwar between hackers purportedly from Arab nations including Saudi Arabia, and their counterparts in Israel.

In recent weeks, hackers have posted the details of tens of thousands of Israeli credit cards online and blocked access to Israeli websites, including that of the Tel Aviv Stock Exchange.

Israeli hackers have responded by targeting Saudi credit cards and websites in the kingdom and elsewhere.