Nuclear disarmament campaign group ICAN won the Nobel Peace Prize on Friday for its efforts to rid the world of the atomic bomb, warning that Donald Trump's presidency showed how dangerous the weapons of mass destruction truly are.

More than 70 years since atomic bombs were used on the Japanese cities of Hiroshima and Nagasaki, the Nobel committee sought to highlight ICAN's tireless non-proliferation efforts as nuclear-related crises swirl around North Korea and Iran.

The decision sent a strong message at a time when Trump has threatened to tear up a 2015 deal curbing Iran's nuclear abilities. And the US president last month alarmed delegates at the UN General Assembly by warning he may be forced to "totally destroy" North Korea because of its atomic weapons programme.

"We live in a world where the risk of nuclear weapons being used is greater than it has been for a long time," said Norwegian Nobel committee president Berit Reiss-Andersen in announcing the prize in Oslo.

"Some states are modernising their nuclear arsenals, and there is a real danger that more countries will try to procure nuclear weapons, as exemplified by North Korea."

But she stressed that the committee's decision wasn't aimed at any particular world leader, adding: "We're not kicking anyone's leg with this prize."

Founded in Vienna in 2007, ICAN (the International Campaign to Abolish Nuclear Weapons) comprises more than 400 NGOs and has mobilised supporters and celebrities alike in its cause.

It was a key player in the adoption of a historic nuclear weapons ban treaty, signed at the UN by 122 countries in July.

However, the accord was largely symbolic as none of the nine known world nuclear powers put their names down. It still needs to be ratified before entering into force.

The US, Russia, Britain, France, China, India, Pakistan, Israel and North Korea are all thought to possess weapons of mass destruction.

Speaking to reporters in Geneva, ICAN's head Beatrice Fihn said Trump's movements over North Korea and Iran showed the clear danger posed by nuclear arms.

"The election of President Donald Trump has made a lot of people feel very uncomfortable with the fact that he alone can authorise the use of nuclear weapons," she said, adding that the US leader has a track record of "not listening to expertise."

'Great global tension'

Although global atomic weapons stockpiles have plummeted - from around 64,000 warheads in 1986 at the height of the Cold War to more than 9,000 in 2017 according to the Bulletin of Atomic Scientists (BAS) - the number of nuclear-armed nations has grown.

Friday's award - the climax to a week of prize-giving honouring global luminaries in the fields of physics, chemistry, medicine and literature - comes as a global nuclear deal with Iran is under increasing pressure from Trump.

The agreement struck in 2015 between Iran and world powers drastically curbed Tehran's nuclear enrichment capability in return for a lifting of punishing economic sanctions. Iran denies ever pursuing a bomb, insisting its nuclear programme is for peaceful energy production only.

But Trump has threatened to bin the accord altogether, and on Thursday criticised Iran's behaviour, telling military leaders in Washington that Tehran has "not lived up to the spirit of the agreement".

The US leader, who has labelled the deal an "embarrassment", is planning to decertify it, the Washington Post and the New York Times reported Friday, potentially paving the way for renewed sanctions on the Islamic republic.

Tensions have also soared between the US and North Korea, which has test-fired two missiles over Japan and conducted a string of apparent underground nuclear tests this year.

"This is a time of great global tension, when fiery rhetoric could all too easily lead us, inexorably, to unspeakable horror," ICAN said.

'Shared commitment'

EU foreign affairs chief Federica Mogherini also congratulated ICAN, tweeting: "We share a strong commitment to achieving the objective of a world free from nuclear weapons."

But Russia, which according to BAS has the world's largest atomic stockpile, said there was no alternative to "nuclear parity" to guarantee world peace.

"Russia is a responsible member of the nuclear club," a spokesman for President Vladimir Putin told reporters in Moscow.

The Nobel committee has rewarded anti-nuclear weapons drives on several previous occasions, handing out the prestigious prize to Soviet dissident Andrei Sakharov in 1975, the international non-proliferation IPPNW group in 1985, and the IAEA's then head Mohamed ElBaradei 20 years later.

More than 300 people and organisations were thought to have been nominated for this year's Peace Prize, including the UN's refugee agency UNHCR, Syria's White Helmets rescue service and Congolese doctor Denis Mukwege.

The Peace Prize, which comes with a gold medal and a cheque for nine million Swedish kronor (943,000 euros, $1.1 million) will be presented in Oslo on December 10, the anniversary of the death of its founder, Swedish philanthropist and dynamite inventor Alfred Nobel.