Since 1945, when the United Nations was founded, the Soviet Union and Russia have used their veto at the Security Council 120 times, the United States 76 times, Britain 32, France 18 and China only five.
The word "veto" is actually never used in the United Nation's charter.
For a resolution to be passed, it needs nine votes in favour from the 15 members of the council, five permanent and 10 non-permanent. These nine votes in favour must include the "concurring votes of the permanent members", the charter says.
The veto power of the permanent members has been widely criticised.
THE VETO RECORD
USSR/Russia: 120 vetoes. Only two vetoes since the collapse of the Soviet Union
US: 77 vetoes. Blocked 36 resolutions criticising Israel.
UK: 32 vetoes, 23 times with the US. All solo UK vetoes on Zimbabwe
France: 18 vetoes, 13 with the US and UK
China: 5 vetoes
The heavy use of the veto by the Soviet Union and the United States have gone a long way to discrediting the veto system.
The threat to use the veto can often sink a draft resolution. In the run-up to the Iraq war in March 2003, France and Russia indicated that they would not support a new resolution sanctioning war. As a result the US, UK and Spain withdrew their draft, and went to war without specific UN backing.
During the Cold War the Soviet Union used to veto UN resolutions almost as a matter of course.
More recently, the US has used its veto regularly to shield the Israeli Government from international criticism or attempts to restrain the behaviour of its military.
The veto and its critics
Critics of the system also point out that among those resolutions that do actually make it onto the books, not all are enforced.
The other main criticism of the veto system is that the permanent five, in effect the victors of World War II, do not reflect the geopolitical realities of today.
"Mr Nyet": The USSR's Andrei Gromyko blocked dozens of resolutions as a matter of course
Were the veto to be abolished, the majority view at the council would prevail and we might expect more resolutions passed, more situations identified as threats to world security, more cases of states being reprimanded and sanctions being imposed.
This assumes that a new, reformed Security Council would have widely respected powers of enforcement and the funds to carry out its will - the current permanent five council members supply a little under half of the UN's overall budget.
None of the existing permanent council members have indicated that want to surrender their veto. Changes to the UN's charter have to be approved by all five permanent members.
So familiar was a Soviet veto in the early days of the UN that Andrei Gromyko, foreign minister between 1957 and 1985, became known as "Mr Nyet", Mr No.
During the first 10 years of the UN the Soviet Union used its veto 79 times. In the same period China used the veto once, France twice and the others not at all.
The Soviet Union came to use its veto less and less, however.
Since the collapse of the Soviet Union in 1991, the veto has been used by Russia only twice - once to block a resolution criticising Bosnian Serb forces for denying the UNHCR access to Bihac in Bosnia and once to block a resolution on the finances of UN operations on Cyprus.
Eight of the last 10 vetoes at the Security Council have been by the United States, and seven of these have been of draft resolutions criticising the Israeli Government in some way.
Most recently, in September 2003, the US vetoed a resolution drafted by Syria that denounced Israel's threat to "remove" Palestinian leader Yasser Arafat. Washington said the resolution was "flawed" because it did not include a "robust condemnation of acts of terrorism" by Palestinian militant groups.
In December 2002, the US blocked a draft resolution criticising the killing by Israeli forces of several United Nations employees and the destruction of the World Food Programme warehouse in the West Bank.
In total, the US has blocked 36 draft resolutions on Israel.
Washington first used its veto in March 1970. Along with the UK it blocked a draft resolution on what was to become Zimbabwe.
The US has vetoed 10 resolutions criticising South Africa, eight on Namibia, seven on Nicaragua and five on Vietnam.
It has been the lone voice in blocking a resolution 54 times.
Of Britain's 32 vetoes, 23 have been on draft resolutions also vetoed by the United States, and 14 also vetoed by France.
The most recent UK veto was in 1989, when the US, France and Britain vetoed a resolution deploring the US military intervention in Panama.
The UK has gone out on a limb, by vetoing a resolution alone, only seven times. The most recent solo veto was in 1972 and all seven were on the situation in Rhodesia, later to become Zimbabwe.
Thirteen of France's 18 vetoes have been on resolutions also vetoed by the US and UK.
France has vetoed two resolutions alongside the UK - both on the Suez crisis in 1956.
Only two resolutions have been vetoed by France on its own - one on 1976 on a dispute between France and the Comoros and the other on Indonesia in 1947.
In 1946, France and the USSR vetoed a resolution on the Spanish Civil War.
Between 1946 and 1971, the Chinese seat at the Security Council was occupied by the Republic of China (Taiwan), which used its veto once to block Mongolia's application for UN membership.
China vetoed resolutions twice in 1972: once to block Bangladeshi membership and once, with Russia, on the situation in the Middle East.
Other vetoes were in 1999 blocking the extension of the mandate of United Nations Preventive Deployment Force in Macedonia and in 1997 blocking the sending of 155 UN observers to Guatemala to verify a ceasefire.