UN ambassador Susan Rice votes at a security council meeting on imposing a fourth round of sanctions against North Korea. Photograph: Spencer Platt/Getty Images

The United Nations security council has voted unanimously to punish North Korea for last month's nuclear test with a toughened sanctions regime, hours after Pyongyang threatened to unleash a pre-emptive nuclear strike on the United States.

Secretary general Ban Ki-moon, a former South Korean foreign minister, said the resolution "sent an unequivocal message to [the North] that the international community will not tolerate its pursuit of nuclear weapons".

The decision by the 15-member council followed lengthy negotiations between the United States and China, the North's main ally. Measures range from tightened financial restrictions to cargo inspections and an explicit ban on exports of yachts and racing cars to the North, but experts say the real issue is enforcement.

China's UN ambassador Li Baodong said Beijing, Pyongyang's main trading partner, wanted to see "full implementation" of the resolution.

Susan Rice, the US ambassador to the UN, told reporters that the measures would "bite hard". She added: "North Korea will achieve nothing by continued threats and provocations."

A foreign ministry spokesman in Pyongyang threatened to launch "pre-emptive nuclear strikes on the headquarters of the aggressors" because Washington was pushing to start a nuclear war against it, in a statement hours before the UN vote.

Experts do not believe the North has managed to produce a warhead small enough to be mounted on a missile that could reach the US. They also pointed out that the original Korean language version referred to "invaders" rather than merely the "aggressors" of the English translation.

Jennifer Lind, assistant professor of government at Dartmouth College in New Hampshire, said that while the statement was disturbing, "North Korea has a long history of bluster and issuing threats that of course it does not carry out, [such as] its long term threats of turning Seoul into a sea of fire."

Earlier this week the North threatened to cancel the 1953 armistice that ended the Korean War.

Thursday's resolution condemns the North's third nuclear test "in the strongest possible terms" as a flagrant breach of previous resolutions, which bar it from testing or using nuclear or ballistic missile technology and importing or exporting material for the programmes.

It aims to hinder those programmes but also targets the ruling elite. A ban on luxury exports was introduced in 2006, but countries could decide what fell under that rubric; this time, specific items are identified.

The resolution warns the North against further provocations and demands its return to the Nuclear Nonproliferation Treaty. But it also stresses the council's commitment "to a peaceful, diplomatic and political solution" and urges a resumption of six-party talks.

All countries are required to freeze financial transactions or services that could contribute to the North's nuclear or missile programmes. Public financial support for trade deals that could assist the programmes is outlawed.

http://www.guardian.co.uk/world/2013/mar/07/north-korea-threat-un-sanctions