Seadrill has delayed the delivery of two drillships it has under construction at Korea's Samsung Heavy Industries until the end of the first quarter of 2017.

It has also deferred the deliveries of eight jack-up drilling rigs into 2016 and 2017.

Seadrill has made a series of delays to avoid taking delivery of new vessels without first having employment contracts in place. The offshore drilling market continues to be weak, caused by falling oil prices, cuts in spending by oil majors and oversupply of new rigs.

The two delayed drillships, West Draco and West Dorado, were originally scheduled for delivery this year. Both are sixth-generation DP3 vessels, able to drill in water of up to 3,600 metres depth. The vessels each had contract value of around US$600m when they were ordered in 2014.

The eight jack-up rigs are being built at China's Dalian shipyard and will be delayed by around a further 44 months, which was agreed with the yard in February.

The NYSE-listed drilling contractor in February agreed with the Cosco (Nantong) shipyard to delay delivery of its Sevan Developer semi-submersible drilling rig. The rig's arrival was initially delayed by 12 months, with cancellation options at six month intervals with the potential to delay delivery by up to 36 months.