By Roger Hardy Middle East analyst

Reports from Israel say that if the country were attacked by Iraq with chemical or biological weapons, it could respond with a nuclear strike.

The reports follow remarks by the head of the Israeli air force warning that, in the event of an Iraqi attack, Israel would not show the restraint it exercised in the Gulf War of 1991.

Such warnings are designed to deter the Iraqi leader Saddam Hussein - and also to send a strong signal to Washington

During that conflict, Iraq fired Scud missiles at Israeli cities.

The report, by Israel's leading defence commentator, Zeev Schiff, is published in the newspaper Haaretz.

Mr Schiff says that if Israel were to suffer massive civilian casualties as a result of a non-conventional Iraqi attack, it could resort to nuclear retaliation.

This - he says - would eradicate Iraq as a country.

Journalistic device?

He quotes as his source testimony given last week to a Senate committee in Washington - testimony he believes was based on US intelligence assessments.

Iraqi missiles struck Tel Aviv in 1991

But this may be a tried and tested device used by the Israeli media.

Israel does not explicitly acknowledge it has nuclear weapons, and so journalists quote a foreign source to publish something they believe to be true.

The report covers a worst-case scenario.

There may not be a high probability of it actually materialising.

But what is clear is that, in any new war with Iraq, Israel would not display the uncharacteristic restraint it showed - under strong US pressure - in 1991.

This was spelt out on Israeli television on Wednesday by the air force chief Major General Dan Halutz.

He did not say how Israel would respond to an Iraqi attack, but made it clear that it would.

Such warnings are designed to deter the Iraqi leader Saddam Hussein - and also to send a strong signal to Washington that, in the early phase of any operation against Iraq, Israel expects the Americans to neutralise any Iraqi missiles which might threaten Israeli cities.