DUBAI, July 25 (Reuters) - Saudi Arabia has hired Goldman Sachs to manage the sale of a stake in Riyadh airport, the first major privatisation of an airport in the kingdom, three sources familiar with the matter said.

The Saudi Civil Aviation Holding plans to sell a minority stake in Riyadh's King Khalid International Airport, the sources said, without providing a timeframe for the sale.

The exact size and potential value of the stake were not immediately known, but Riyadh has the second biggest airport in Saudi Arabia after Jeddah's King Abdulziz International Airport.

Officials have highlighted transport as a priority sector for privatisations as Saudi Arabia looks to reduce government spending, improve services and diversify its oil dependent economy.

However, the process has taken time to get underway. The kingdom had said in November 2015 it expected to begin privatising airports in the first quarter of 2016.

Saudi Civil Aviation Holding was set up to manage the privatisation process, the Saudi General Authority of Civil Aviation (GACA) says on its website. GACA did not respond to a request for comment on the Riyadh airport stake sale.

King Khalid International Airport handled 22.5 million passengers in 2016, up 0.9 percent year-on-year.

Saudi Arabia is trying to raise $200 billion over the next several years through stake sales in assets such as airports.

The government has also brought in foreign firms to manage some of its airports including the Dublin Airport Authority (DAA), which was awarded in 2016 the contract to manage and operate Riyadh airport's new Terminal 5.

Singapore's Changi Airport Group was awarded in April a contract to operate the King Abdulaziz International Airport (KAIA )in Jeddah for up to 20 years.

Goldman's role comes at a time when investment banks are stepping up their presence in Saudi Arabia to capitalise on the country's privatisation programme such as Aramco's planned $100 billion initial public offering next year.

Goldman Sachs recently applied to Saudi Arabia's capital markets regulator for a licence to trade equities in the kingdom, Reuters reported in June.

A Goldman Sachs spokesman in London declined to comment. (Additional reporting by Alexander Cornwell and Reem Shamseddine; Editing by Mark Potter)

© Reuters News 2017