The soothsayers surrounding Than Shwe, the paranoid general at the apex of Burma's monstrous military regime, are in high favour. Their prophecies of civil unrest followed by a great natural disaster swayed his decision three years ago to move the capital north to Naypyidaw (“abode of kings”), an isolated eyrie remote from storm-blasted Rangoon and the fetid sea of devastated or obliterated townships, bloated corpses and destitute survivors that the fertile Irrawaddy delta has become.

Naypyidaw was untouched by Cyclone Nargis. The only “damage” was to the telephone, on which Than Shwe was said to be unable to take calls all week, not even from Ban Ki Moon, the UN Secretary-General. A good omen in the generals' eyes, this immunity is an awful omen for the stricken Burmese. Naypyidaw's lucky escape can only reinforce the regime's determination to put self- preservation first, even if this means that up to a million more people die, needlessly, denied access to readily available international relief.

The junta is not, of its own volition, going to let in anything like the volume of aid required, at the speed required, to prevent a natural disaster turning into a monstrous, and manmade, humanitarian catastrophe. It does not admit, perhaps not even to itself, the deadly truth. The official and implausibly precise toll has inched upward to 28,458 dead and 33,416 missing. Yet according to the army's Irrawaddy divisional headquarters, the cyclone killed around 50,000 in or near Bogalay, where 142 villages were submerged; another 20,000 in Labutta; and at least 10,000 in Pyapon. Four out of 400 survived in Khaing Shwe Wa village; in hundreds more villages not a trace of life remains. Remoter areas cannot yet be reached, but in these three districts alone more than 700,000 are without shelter, food or corpse-free water; untreated wounds are turning septic, infant dysentery is rife, and cholera, already reported, could rapidly become epidemic.

The generals don't want to know. At Thilawa port, rice for Bangladesh was loaded on to a container ship late last week and the regime insists that it will meet all its export commitments. The only rice released to victims, in handfuls, from the port's warehouse was rotted by flood damage. The state media, parroting the lie that Burma is returning to normal, has switched to “reporting” massive turnout in Saturday's constitutional referendum, which Than Shwe unconscionably refused to postpone - those soothsayers again, no doubt.

This constitution's sole and unconstitutional purpose is to perpetuate the junta's illegitimate rule and forever exclude Aung San Suu Kyi, the symbol of Burmese aspirations to democracy. Few Burmese have read it and fewer still dare to oppose it: the penalty is a three-year prison sentence.

Troops and trucks galore were available to police this anti-democratic farce, just as they were to beat the hell out of last year's uprising; but there has been no mobilisation for disaster relief.

So far the world has confined itself to pleading with the junta, and pleading has got nowhere. The driblet of aid allowed is slowly becoming a trickle, but for thousands it is already too late, and for millions more this is nowhere near enough. What little has got in has been impounded or, in the case of trucks of emergency plastic sheeting delivered from neighbouring Thailand by the UN Commission for Refugees, just dumped near a pagoda close to the frontier. This refusal of international humanitarian aid is, the UN laments, “unprecedented”. Unprecedented - or almost unprecedented - decisions are called for.

Governments with the power to help must insist on doing so, with or without the junta's co-operation - with the approval of the UN Security Council if they can, and without it if they must. Governments had the approval neither of Saddam Hussein nor the Security Council in 1991, when they airlifted aid to fleeing Kurds in northern Iraq. The idea that states can do what they please within their borders has been modified since 1945 by a growing acceptance that states have responsibilities as well as rights, and that gross violations of those responsibilities are an international concern. Forcing aid on the regime would be a risky venture; but to cite sovereignty as the reason why nothing can be done without its assent would be to let this foul regime get away with mass murder.

Bernard Kouchner, the French Foreign Minister and founder of Médecins Sans Frontières, has called on the Security Council to insist on humanitarian access to Burma. He invokes two principles: the “right to intervene” in catastrophic situations, accepted by the General Assembly in the 1990s; and the “responsibility to protect” victims of genocide, ethnic cleansing, war crimes and crimes against humanity. This advance in international law was unanimously endorsed by all UN member states at the UN's 60th anniversary summit in 2005, The fact that many governments now regret that endorsement is testament to the power of the concept. In essence, it is about getting states to accept “help” to change their ways, implicitly backed by the threat of military intervention.

History is on Mr Kouchner's side. This is an idea whose time has come, and Burma's agony is a test of the UN's moral and political authority.

Predictably, France is opposed by China, Russia and, with Zimbabwe in mind, by South Africa. China even had the gall to suggest that the Burma crisis is no worse than the French heatwave in 2003. Shamefully, the usual suspects are supported by Indonesia - whose experience of the 2004 tsunami taught it that every hour's delay costs lives, but which demurs at “politicising” a “technical” matter.

Still more shamefully, the British Government, which chairs the Security Council this month, is sitting on the fence, muttering that the responsibility to protect was devised for terrible crimes, not terrible disasters, even though the disaster now unfolding is palpably attributable to criminal negligence on the junta's part.

Mr Kouchner is undaunted. He has dispatched 1,500 tonnes of aid on the Mistral and insists that France will distribute it directly to the victims. Britain, Australia and the US should go where he leads, and plan to move in directly, if all else fails. Better that than impotently counting rice sacks in Thai warehouses. If the generals get the message that “no” will not be taken for an answer, they may decide to join what they can't beat. And if not? Imposing aid is a messy business. Dying for lack of it is messier by far.

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