Saudi Arabia is striving to develop a homegrown defence industry but cutting reliance on foreign equipment will take years, the head of a major military development firm said Thursday.

The kingdom is the world's third-biggest defence spender, but only two percent of that outlay is local.

Riyadh targets 50 percent domestic defence content by 2030, under a wide-ranging vision to diversify the oil-dependent economy.

"It's going to take some time to put it into practice. You're talking about a few years down the road," Mohamed Al-Mady, governor of the kingdom's Military Industries Corporation, told AFP when asked how soon products could be available.

It is too early to say what type of gear the kingdom could manufacture because a "final strategy" is still being developed, he said.

"Then we will know exactly which sectors" will be the focus, Mady said on the sidelines of the Asbar World Forum in Riyadh.

The Saudi defence industry currently consists of just seven companies and two research and development centres.

It has already begun developing spare parts, armoured vehicles and ammunition but will expand "to higher value and more complex equipment such as military aircraft," according to the kingdom's economic diversification plan, known as Vision 2030.

With the strategy still evolving, Mady could not say whether aircraft production was a realistic goal.

Since March last year, the kingdom has spent billions of dollars on a military intervention against rebels in Yemen, where it leads an Arab coalition supporting the country's internationally recognised government with air strikes and other aid.

Saudi Arabia has traditionally bought its arms from the United States, Britain and France.

"We visited a number of countries around the world to learn from their experience" in defence manufacturing, Mady told the forum, specifically citing South Korea and Turkey.

"We need all types of products that we brought from outside," said the former vice chairman and CEO of Saudi petrochemicals giant SABIC.

"We have to manufacture them locally."