A flare is still alight on Total’s Elgin Platform, which was evacuated following a gas leak on Sunday.
Total, which operates the offshore platform, said the wind is blowing the gas plume in the opposite direction to the flare.
All 238 workers were evacuated from the company's Elgin PUQ platform, about 150 miles off the coast of Aberdeen, following the discovery of the leak on Sunday. It could take as long as six months to drill a relief well to stop the release of gas.
An exclusion zone of two nautical miles has been set up around Elgin, with ships and aircraft ordered to stay away from the area.
Last night it emerged that a flare is still burning on the installation.
David Hainsworth, health, safety and environment manager for Total, told BBC Newsnight Scotland: "The flare is still alight on the main production platform, however the wind is blowing the gas plume in the opposite direction away from this flare.
"We know the weather forecast is such that the wind direction remains the same for the following five to six days and we're evaluating options to extinguish this flare."
A coastguard spokesman said flares on offshore platforms are commonly used to burn excess hydrocarbon gases that the rig does not use or capture.
Total E&P UK, which operates the Elgin platform, said it was taking "all possible measures" to try to identify the source and cause of the leak and to bring it under control. It is looking at various options on how to stem the release of gas.
Shell has reduced its workforce on two offshore installations close to the Total platform as a precaution.
Around 85 staff have been taken off the company's Shearwater platform and the nearby Noble Hans Deul drilling rig, leaving a workforce of 117 people.
Shell also said it has brought forward plans for maintenance at Shearwater and is shutting down production in a "controlled manner".
A sheen on the water is present near the platform, estimated to extend over 4.8 square kilometres (1.85 square miles) and measure between two and 20 tonnes in volume.
Total said its preliminary assessments indicate there has been no significant impact on the environment because of the leak.
Offshore union RMT welcomed the quick evacuation of the platform but warned there could still be serious consequences.
RMT offshore organiser Jake Molloy said: "Total acted very swiftly in getting everyone off but the potential still exists for catastrophic devastation.
"If the gas cloud somehow finds an ignition source we could be looking at complete destruction.
"This is an unprecedented situation and we really are in the realms of the unknown but the urgent need now is to find a way of stopping the flow of gas."
RSPB Scotland called for transparency from Total.
Director Stuart Housden said: "We hope that, second to minimising risks to people, environmental considerations will be foremost in the mind of Total when considering their response to this situation.
"We urgently need to know exactly what environmental impacts the leaking substances could have."
The Scottish Government said it is monitoring the developments.
Environment Secretary Richard Lochhead said: "As the situation currently stands, impact on the environment, which is the Scottish Government's area of responsibility, is minimal."
Total E&P UK said it has met with the Secretary of State's representative, the Health and Safety Executive, the Department of Energy and Climate change, Marine Scotland and the Coastguard.
Energy Minister Charles Hendry told BBC Scotland's Good Morning Scotland programme that there were reasons for burning the flare and said he has been told that it can be shut down remotely if there is a problem.
He said: "Clearly, when you have a significant amount of gas escaping, there is a case for trying to burn some of it off to get rid of it rather than leaving it as a hazard elsewhere, so there has to be a decision made on the balance between safe operation and flaring off the gas that can be flared off and closing down the full platform."
Hendry added that he was "very comfortable" with the agreed emergency plan for Elgin.
He said: "The focus of that first of all is on human life and removing people from the platform, which was done; the second is on an exclusion zone; and thirdly moves on to securing the platform and trying to remedy the problem."
Lochhead said Total should be providing more information on the situation.
He said: "This is an abandoned platform hundred of miles out at sea and it's a very serious situation and of course we can't go out and see it for ourselves so we need the company to put all the relevant information into the public domain and have absolute transparency.
"I'm also asking today both the UK Government and the oil company to put the information on how they calculate these risks into the public domain as well."
Hendry could not put a timescale on stopping the leak and said a "range of options" were being explored.
He said: "We should remember that this is an abandoned well that the gas has largely been depleted from - it had previously been plugged and it was during the process of long-term decommissioning that this has happened so this is not a high-pressure well that we see in other areas of the North Sea, but, nevertheless it is very difficult to close it down completely.
"We have in place the emergency plans and these are documents that can be viewed, and these contribute to the North Sea being the most robust safety regime in the world - something which the Americans recognised after the Gulf of Mexico.
"We will not compromise on safety - we recognise that this work is hazardous but we have learned from past experiences and disasters and we do believe that the approach that we now have is the most robust that you will find anywhere."
Lochhead said the leak should be seen as "warning sign" to ensure safety at sea, particularly as further deep-water operations have been approved.
He said: "The oil industry is very important to Scotland and we're not wanting to stop further developments but what we need to do is to make sure that the proper safety regimes are in place."