Offshore giant Total has finally stopped the gas leak on its Elgin platform.
An operation to pump heavy mud into a leaking North Sea well has been a success, according to the French energy firm.
But shares in the company have lost 16% of their value – more than £10billion – since the gas leak started.
Last night, Total president Yves-Louis Darricarrere said the company had reached a “turning point” in tackling the incident.
All 238 staff were evacuated from the platform when the leak was detected in late March.
At one point, about 7million cubic feet of gas was leaking every day, but this was estimated to have been reduced by two-thirds when workers started drilling a relief well last month.
Total was granted approval from the Department of Energy and Climate Change (DECC) almost two weeks ago to carry out the “kill” operation.
The firm said experts would continue to monitor the well in the coming days to confirm the intervention’s “complete success”.
Mr Darricarrere, Total’s president of exploration and production, said: “Today a major turning point has been achieved. Our absolute priority was to stop the gas leak safely and as quickly as possible.
“Since March 25, we have been working closely with the authorities and we have communicated transparently and will continue to do so.
“We shall now fully complete the ongoing task and take into account the lessons learned from this incident.”
Scottish Environment Secretary Richard Lochhead said: “This is clearly good news from Total that the initial efforts to stop the Elgin gas leak appear to have been successful.
“Further monitoring will be needed to ensure that this is a lasting solution, but this is a welcome step in the right direction.”
Energy Minister Charles Hendry said the UK Government would continue to monitor the situation closely.
“The fact Total has managed to stop gas leaking from the Elgin platform is clearly excellent news,” he said.
“We will continue to monitor the success of the operation closely to ensure that the well can now be safely and permanently secured.”
Sir Robert Smith, MP for Aberdeenshire and Kincardine and senior member of the energy and climate change select committee at Westminster, said all firms must learn from the incident.
He said: “It is clearly crucial that all lessons are learned to avoid a repeat of such an incident – and that these lessons are shared with all other operators.”