Hundreds of tons of oil could still be inside an offshore pipeline which has been leaking for a week off the Scottish coast, raising the possibility that Britain's worst oil spill for a decade could worsen.
As oil giant Royal Dutch Shell continues to try to stem the flow on the seabed about 112 miles east of Aberdeen, the company said there is still a risk an estimated 660 tons of oil that remain in the pipeline could leak out.
"We are talking about hundreds of tons of additional oil in the pipeline that we need to preserve and keep there," Shell technical director Glen Cayley said.
"Until we have completely eliminated the leak and secured this pipeline, I would say there is still risk."
Oil leaked into the sea off the coast of Scotland for a seventh day yesterday as Shell said it was planning extensive activity including the deployment of divers to stop completely the flow of oil.
Richard Lochhead, the Scottish Environment Secretary, urged Shell to be more open with the public yesterday after it emerged that an estimated 218 tons of oil, equal to 1,300 barrels, have already spilt from the pipe.
"I stressed, once again, the importance of clear communication on the current operation and the expectation people have for complete openness and transparency on the situation."