A top Israeli official said he was unaware of a disputed German deal to sell hundreds of tanks to Saudi Arabia but had complete confidence in the German government, in an interview published Thursday.

Saudi Arabia is reportedly about to buy 200 Leopard-2s, Germany's main battle tank which is also produced under licence in Spain, for a multi-billion-euro (dollar) sum.

Germany, which for more than 20 years has declined to sell such heavy weapons to Saudi Arabia because of concerns over human rights and fears for Israel's security, has refused to officially confirm the reports citing a secrecy policy on such deals.

While a German newspaper said this week that both Israel and the United States had signed off before the final decision was made on June 27, Israeli deputy foreign minister Daniel Ayalon said he did not know of a purchase.

"First let me stress that I am unaware of an upcoming tank deal between Germany and Saudi Arabia," he told the German daily Die Welt.

"It is in the nature of such matters that one does not speak about them publicly. But I can assure you that we fully and completely trust Germany's government."

Ayalon said that Israel and Germany shared "trusting, constructive and friendly" relations, adding that Berlin was his country's "most important ally in Europe".

"Germany's commitment to the security and well-being of the state of Israel and its people means a lot to us," he said, in remarks published in German.

Asked whether a tank sale to Saudi Arabia was a way to keep Iran in check, Ayalon said: "I think the entire international community must take action against Iran... It is not only a threat to Israel but rather poses a global danger.

"We must keep it from going on the offensive in the Middle East, with economic sanctions and political pressure."

German opposition politicians and even members of Chancellor Angela Merkel's ruling centre-right coalition have slammed the reported tank sale, particularly in light of democratic uprisings throughout the Middle East.

Selling tanks to Saudi Arabia at a time when that country has sent armoured vehicles to help put down a peaceful protest movement in neighbouring Bahrain is "a slap in the face for freedom movements in the whole region," Social Democrat parliamentary deputy leader Gernot Erler said this week.

Meanwhile the opposition Green party said it would file a lawsuit against unnamed executives at the tank manufacturer Krauss-Maffei Wegmann in a move to force the German government to shed light on the matter.

A parliamentary whip, Volker Beck, told Friday's upcoming issue of the daily Sueddeutsche Zeitung that the suit was based on suspicion that selling the tanks to Riyadh would violate arms export laws.