Shell is removing workers from two offshore installations close to a Total platform which has been evacuated after a gas leak.

The leak on the Elgin PUQ platform, about 150 miles (240km) off the coast of Aberdeen, led to the evacuation of all 238 workers.

Total E&P UK (TEP UK), which operates the 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 has been confirmed that there is a sheen on the water near the platform.

Oil Spill Response (OSRL) on Monday carried out two aerial surveillance flights to assess the situation and two further flights were planned for Tuesday.

Shell said it is removing 85 staff from its Shearwater platform and the nearby Noble Hans Deul drilling rig as a precautionary measure.

They are around four nautical miles (4.6 miles) from the Elgin platform.

Drilling operations on the Noble Hans Deul rig have been suspended and the wells have been left in a safe state, Shell said.

A Shell spokesman said: “While the move is purely precautionary and primarily driven by the prevailing weather conditions, and both facilities remain operational, it has been decided to reduce numbers to a more manageable level until the full situation surrounding the Elgin leak has been established.”

Shell is removing 52 workers from Shearwater, leaving 38 on board, while 33 are being taken off the Hans Deul, leaving 79.

Following the discovery of the leak on Sunday 219 staff were evacuated from the Elgin platform.

Nineteen core crew were initially left on board but were taken off overnight between Sunday and Monday and flown to Aberdeen.

There have been no reports of any injuries.

Aberdeen coastguard co-ordinated the evacuation of the Elgin platform.

Coastguard watch manager Kevin Brown said three rescue helicopters and four civilian helicopters helped with the process.

TEP UK said it has met the secretary of state’s representative, the Health and Safety Executive, the Department of Energy and Climate change, Marine Scotland and the coastguard.

The company said it has also mobilised experts from elsewhere in the Total Group to offer additional assistance and help deal with the incident.

In a statement the company said: “Total E&P UK confirms that the gas leak at the Elgin Well Head Platform remains ongoing, although the situation is currently stable.

“We continue to take all possible measures to try to identify the source and cause of the leak and to bring it under control.”

The company said the precise cause of the leak remains unclear.