The fact that Russia and China voted with the US offers a glimmer of hope, writes former foreign correspondent Mary Dejevsky

It is not every day that the UN security council passes previous resolutions unanimously. But that is what happened on Saturday, when it approved resolution 2371, which provides for much tougher sanctions against North Korea, including a ban on it selling coal, iron and lead.

The big question, which remained open until the vote actually has just taken place, was which style China would go. A veto was unlikely, but abstention on measures that could if only marginally impair Chinas economy and potentially reduce Beijings leverage with its northern neighbour was eminently possible.

In the end, China appears to have calculated that security threats from North Koreas growing nuclear weapon ability overrule any other considerations. It may also have factored in the opprobrium that China could face if it stood aloof, and the goodwill it could win by joining the international consensus.

Russias vote could not be taken for granted either. While it has long assured a nuclear-capable North Korea as a threat, Moscow has rarely built international clubbability a priority, and the new US sanctions, signed by President Donald Trump last week, scarcely promoted cooperation. Like China, though, Russia chose to focus on the greater danger.

The result is an illustration of how the international system should work, and how in recent memory it so rarely has. The consequence is both to increase North Koreas isolation and to ramp up the cost to Pyongyang of its nuclear programme. The referendum also presents the Trump administration with something akin to a diplomatic triumph.

The resolution was a direct response to North Korean missile tests that appeared to bringing the US within scope for the first time. America has not always been adept at lining up international, still less UN, support for its own concerns, but this time around it succeeded.

And a few reasons can be hazarded as to why. One is some shrewd preparation by secretary of state Rex Tillerson. Even as rumors circulated that he might be about to leave his job in annoyance, he turned up at the state department last week to address the media with a message that was clearly aimed first of all for North Korea and its neighbours.

What Tillerson said was this: We do not attempt a regime change; we do not seek the collapse of the existing regime; we do not try an accelerated reunification of the peninsula; we do not attempt an excuse to send our military north of the 38 th parallel. In so doing, Tillerson addressed head on at least some of the concerns that surely underlie North Koreas pursuit of nuclear weapons.

In sharp contrast with the belligerence heard from both sides in recent months, Tillerson also made an offer albeit conditional of direct talks and a possible security guarantee. While it is unrealistic as of now to expect Pyongyang to give up its nuclear ambitions, even creating the future prospects of talks addresses another aspect of North Koreas thinking: that possessing nuclear weapon is the only way it can attract attention.

At the same press conference, Tillerson also offered a small, but significant, concession to China, explicitly absolving it of blame for the situation in North Korea. This was in stark contrast to earlier remarks by Trump, who had suggested that China could solve the problem if it actually wanted to.

The wording of the UN resolution suggests some of the give and take that have been able to persuaded China and Russia to create their hands, rather than abstain. One to continue the theme of talks is its call for a return to the six-party talks, whose ultimate objective was the denuclearisation of the Korean peninsula. North Koreas good faith here was always in question, but with the government in South Korea conveying new interest in diplomacy, and Pyongyangs nuclear programme that much further forward, this may not be as remote a prospect as it seems.

At a day when present trends as evinced by the dissension over Trump, and the UKs departure from the EU seems to be towards broken off rather than coming together, the unanimity shown over North Korea, and the dextrous coupling of carrot and stick, is a positive development. Good news is rare enough in international relations; it deserves to be acknowledged when it happens.

Mary Dejevsky is a former foreign correspondent

Read more: www.theguardian.com