nuclear weapons

The Russian military entered Ukraine from several directions, with troops headed towards its capital, Kyiv, and attacked with airstrikes and shelling. Ukrainian authorities said dozens of soldiers on both sides and some Ukrainian civilians were killed amid the fighting.

UN Secretary General Antonio Guterres described the treaty as a product of increasing concern over the risk posed by the continued existence of nuclear weapons, including the catastrophic humanitarian and environmental consequences of their use.

Since it was opened yesterday, more than 50 countries had signed the treaty which comes into effect in 90 days.

Fiji, Samoa, Tuvalu and Kiribati are among the other Pacific Island nations who have signed, while notable exclusions from the region include Guam and the Marshall Islands.

Foreign Minister Wang Yi said if war occurred there could be no winner.

Mr Wang's comments come as the US voices increasing concern at North Korea's development of nuclear weapons and deploys a Navy carrier group off the Korean peninsula.

China, North Korea's only backer, fears conflict could cause the regime to collapse and problems on its border.

Mr Wang said: "One has the feeling that a conflict could break out at any moment.

“I think that all relevant parties should be highly vigilant with regards to this situation."

The statement, coming just a day after it said it is ready to conduct more rocket launches any time it sees fit, has heightened concerns the North may soon either conduct a launch — which Washington and its allies see as a pretext for testing missile technology — or hold another test of nuclear weapons that it could conceivably place on such a rocket.

The diplomats said at least two other issues still needed final agreement: Iranian demands that a U.N. arms embargo be lifted and that any U.N. Security Council resolution approving the nuclear deal no longer describe Iran's nuclear activities as illegal. 

They demanded anonymity because they are not authorized to discuss the negotiations publicly.