The review involving the 900,000-barrels-a-day offshore project is another sign Saudi Aramco, by far the world’s biggest oil company by output, wants to renegotiate contracts it signed at the height of the commodities price boom.

Saipem, one of Europe’s biggest oil field services companies, did not specify in a statement whether other suppliers or contractors were affected.

A Saudi Aramco spokesman was not immediately available to comment.

Saipem said it still had its contract for onshore development. Shares in Saipem, one of Europe’s biggest oil services companies, plunged on rumours it had lost the contract.

However, Aramco has directed that no further commitments towards suppliers and contractors be taken on pending an analysis “aimed at cost optimisation”, Saipem said in a statement.

Saipem shares closed down 16.64 per cent at 10.37 euros, while shortly after 1800GMT the DJ Stoxx oil and gas index was 1.35 per cent lower.