North Atlantic Drilling (NADL), a subsidiary of Seadrill, will delay the closing of a deal with Russia's Rosneft by two years and has agreed to renegotiate the terms of the agreement, reports Reuters.
NADL will also be permitted to delay the construction, delivery, or shipyard stay of any of those rigs.
Western sanctions levied against Russia for its actions in Crimea have raised concerns over the future of the $4.1 billion agreement and have already forces Rosneft to terminate several North Atlantic Drilling contracts.
North Atlantic Drilling said in a statement, "Today, all parties have mutually agreed to extend the termination date ... whereby any party can terminate the framework agreement and/or any offshore drilling contracts at any time prior to May 31, 2017, at no cost."
The two companies also agreed to renegotiate the terms following the collapse of rig rates caused by the 50% fall in the oil price since June 2014.
Per the terms of the agreement, which in November was first delayed to May this year, North Atlantic Drilling would purchase roughly 150 land rigs from Rosneft. Rosneft, in turn, would acquire a stake of roughly 30% in North Atlantic Drilling. Seadrill, which now holds 71% of North Atlantic Drilling, would remain its majority shareholder.