A historic agreement has been reached over Iran's nuclear programme between Iran and the United States, France, Germany, Britain, China and Russia in what has been a protracted round of negotiations in Geneva. So now the spotlight falls on the most vociferous opponent of the pact that was reached earlier this week - Israel.

Israel's Prime Minister Benjamin Netanyahu had already outdone himself in his efforts to derail the Geneva talks, making liberal use of apocalyptic rhetoric in the attempt.

This has continued in the aftermath of the deal being signed and sealed in Geneva earlier this week, when he had this to say. "Today the world became a much more dangerous place because the most dangerous regime in the world made a significant step in obtaining the most dangerous weapons in the world."

Iran, it should be noted, has never occupied any of its neighbours. It hasn't initiated any war or military conflict in the region and it does not possess nuclear weapons.

Israel, on the other hand, is currently occupying Palestinian land in a clear and ongoing breach of international law. It has initiated military conflict in the region on numerous occasions and possesses an as yet undeclared nuclear arsenal.

Based on these facts it would seem that the word "hypocrisy" has been struck from the vocabulary of Netanyahu and the hawks in his government who take a similarly hostile view of Iran and its role in the region.

When it comes to Israel's nuclear weapons, it is worth recounting the role of Mordechai Vanunu, the Israeli whistleblower who first revealed their existence to the world.

Vanunu was employed as a technician working at Israel's nuclear facility at Dimona in the Negev desert from the mid-1970s to the mid-'80s.

An opponent of Israel's treatment of the Palestinians and the country's invasion of Lebanon in 1982, Vanunu decided to take covert pictures as evidence that Israel was developing nuclear weapons at Dimona.

After leaving Israel he subsequently sold the pictures to the Sunday Times in Britain, which published them after they were verified as genuine by nuclear experts.

By this point Vanunu had settled in Britain. He was lured to Italy by a female Mossad agent posing as a US tourist in Britain.

While in Rome he was kidnapped, drugged and smuggled out of the country and transported back to Israel.

There he was imprisoned for 18 years for treason and espionage, of which he spent more than 11 years in solitary confinement.

Released from prison in 2004, the former nuclear technician has been refused permission to leave Israel and has existed under a de facto state of house arrest.

According to a report issued by US nuclear experts earlier this year, it is claimed that Israel is currently in possession of 80 nuclear warheads with the potential to develop double that number.

The findings of the report - titled Global Nuclear Weapons Inventories - were published in the LA Times in September.

The only surprise in the report's findings was that the number of Israeli nuclear warheads was so low. Previous estimates had ranged from 200 to 300 warheads.

As to the specific nature of Israel's nuclear weapons arsenal, the Stockholm International Peace Research Institute, in its 2013 yearbook, estimated that 50 of Israel's nuclear warheads were for medium-range ballistic missiles, while 30 were designed to be carried and delivered by aircraft.

To date, Israel continues to deny it possesses nuclear weapons. It is not party to the non-proliferation treaty (NPT) on nuclear weapons, unlike Iran.

In addition, Israel has continually denied access to its nuclear facility at Dimona by the International Atomic Energy Agency, the international body charged with regulating the use of nuclear power and policing the NPT.

Opponents of Israel's policies and actions in the Middle East have long accused the West of double standards with regard to the failure to hold the Israel to the same standards as its neighbours throughout the region, including Iran.

Israel asserts its right to exceptional status based on what it describes as an "existential threat to its existence."

When its growing number of critics point out that this claim is unfounded, they are typically accused of anti-semitism. Such accusations have become increasingly discredited with overuse, however.

With Iran having just agreed to curb its nuclear programme in return for the partial lifting of sanctions by the US and its allies and with Syria in the process of destroying its arsenal of chemical weapons, the ability of Israel to maintain both is no longer tenable - and certainly not if international law and justice are to retain any credibility.

The truth is that the greatest cause of instability in the region is Israel with its obdurate refusal to grant justice to the Palestinians and to abide by international law.

In the words of former US president Jimmy Carter, "Israel's continued control and colonisation of Palestinian land have been the primary obstacles to a comprehensive peace agreement in the holy land."