It said on Wednesday its total acquisition of 488,000 shares this month cost it $5.8m.

On 1 December it brought its stake in the supply ship operator to 18% from 17.1%.

“Following the weaker stock market environment in the oil sector”, it has now added another slice to reach 19.2%, it said.

Prices paid in the open market ranged from $12.89 to $10.39