BP plugs its success in finally halting Gulf oil leak

BP today claimed a "significant milestone" in ending the Gulf of Mexico oil disaster when an operation to plug the leak appeared to have worked.

It began pumping a heavy liquid known as drilling mud into the well at 9pm last night — to counter the force of the escaping oil — and this morning announced the well had reached a "stable condition".

There was a further boost for the company with reports that a US government agency had found that three quarters of the leaked oil had evaporated, dispersed or been captured.

But the news had little immediate impact on BP's share price in London which was this morning down 6p to 409p, still more than £1 above its 52-week low.

Today's eight-hour operation involved pumping the mud into the fractured well. The Deepwater Horizon oil rig exploded and sank in April, killing 11 workers, and became the worst marine spill in history.