Turmoil in Egypt spooked oil traders last month, threatening to close the Suez Canal. Now Libya, which accounts for about 2 per cent of global production, seems on the brink of civil war, creating further disquiet. With prices above $100 a barrel, the world must prepare for further oil price volatility – and the threat of a genuine crisis if production is disrupted in Saudi Arabia or elsewhere.

The situation has sent activists and politicians scrambling for their usual answers. Some call for more domestic production; others urge alternatives to oil. But neither will make much difference. Alternatives have potential, but will take decades to arrive at scale. Expanding domestic production is even less promising: new supplies don’t insulate consumers from big changes in world prices, and increase output only slowly. Both are worthy, but we need a plan plans for short-term crisis management too.

Such plans must begin with a coherent approach to strategic petroleum reserves. These can be used as a buffer against global disruptions, meaning that if supply drops, or transit routes are disrupted, stocks are released to calm world markets. The problem is, it is unclear which circumstances justify their use. The current situation does not merit it, the head of the International Energy Agency (IEA) reassured markets they could be used, if needed. If unrest spread to Saudi Arabia a release would make sense, but policy is muddled on more moderate disruptions.