US President Donald Trump has approved an agreement with Saudi Arabia that could potentially provide the kingdom with uranium enrichment capability for its civilian nuclear programme, according to two people familiar with the matter.

The people, who were not authorised to comment publicly about the yet to be formally announced decision, said the agreement is expected to be announced publicly as early as Wednesday.

The deal is expected to last 30 years and is also expected to involve US firms in developing the programme. The deal could allow for the building of a uranium enrichment facility in Saudi Arabia following a joint US-Saudi study.

The White House did not immediately respond to a request for comment on the decision, which was first reported on by the Wall Street Journal.

Both Trump and former US president Joe Biden tried to reach a nuclear deal with the kingdom to share American technology.

But non-proliferation experts warn any spinning centrifuges within Saudi Arabia could open the door to a possible weapons programme for the kingdom, something its assertive crown prince has suggested he could pursue if Tehran obtains an atomic bomb.