"We have informed Soco and urge the government of DR Congo to fully respect the international conventions to which it is signatory," a foreign office spokesperson said in a statement seen by Reuters.

"Foreign investments in sectors such as hydrocarbons... can play a vital role in boosting development of the DRC... Such investment needs to be done responsibly and sustainably, in compliance with local law and conforming to international standards," the statement said.

Soco's deputy chief executive officer, Roger Cagle told the news wire in a statement on Tuesday that the company was involved in the project on the invitation of the Congolese government.