Babylon Health care Services Ltd, the fast-growing mobile medical consultation service, said it raised $550 million to expand into the US and Asia.

The investment includes capital from new investors such as Saudi Arabia’s Public Investment Fund, and valued the company at more than $2 billion, Babylon said in a statement on Friday.

“We have seen significant demand from partners across the US and Asia,’ said Ali Parsa, London-based Babylon’s founder and chief executive officer. ‘While the burden of health care is global, the solutions have to be localised to meet the specific needs and culture of each country.”

Babylon was founded in 2013 and is one of a number of companies racing to create general diagnostic software. Others include Ada, a start-up with offices in Berlin and London that has launched a similar symptom-checker app to Babylon, HealthTap, in Palo Alto, California, and Your. MD, a London start-up that has created a health information app.

The UK’s National Health Service lets patients choose Babylon’s ‘GP in Hand’ mobile consultation service as their official primary care provider, and the start-up last year said its artificial intelligence software, in tests, can assess common conditions more accurately than human doctors. In its statement, Babylon said it now delivered 4,000 clinical consultations a day.

Babylon has come under strong criticism from health practitioners. Last year, Martin Marshall, vice-chairman of the Royal College of General Practitioners, which administers the exam Babylon’s AI sought to benchmark itself against, said no app or algorithm ‘will ever be able to do what a GP does.’ The industry body also criticised the NHS for its partnering with the start-up.

In addition to Saudi Arabia’s PIF, investors include existing backers Kinnevik AB and Vostok New Ventures.

The Saudi sovereign wealth fund is a central part of Crown Prince Mohammad Bin Salman’s effort to wean his country’s economy away from oil under a plan known as Vision 2030. It’s the largest investor in SoftBank Group Corp.’s Vision Fund, with a $45 billion contribution. Bin Salman is also PIF’s chairman.

Goldman Sachs International and Morgan Stanley & Co International Plc advised the start-up on the fund raise.