There are almost 7.5 million foreigners working in Saudi Arabia out of a total population of just 17 million, a proportion the government wants to reduce to 20% within 10 years.
The Manpower Council, in charge of labour policy, said it was becoming increasingly worried about unemployment - previously non-existent, but now close to 400,000 strong, even according to official figures.
The government does not plan to expel expats, but aims to discourage some classes of foreigners from applying for employment.
Already, 34 professions are closed to foreigners; the Manpower Council plans to add another 22 sectors to the list.
Indians hard-hit
The new regulations may not make a difference immediately.
But they could have a dramatic effect on certain groups of expats, since no one country will be allowed to compose more than 10% of the overall foreign population.
At present, there are at least 1.5 million Indians in Saudi Arabia, a population that should be no higher than 200,000 under the proposed regime.
So far, the Manpower Council has given few details on precisely how the policy should be implemented, insisting only that the state and the private sector should work together to employ more Saudis.
Expat worries
Saudi Arabia's huge expat population is the result of its oil wealth, which created a demand for products and services that wealthy Saudis were unwilling to provide themselves.
Sectors such as financial services and the periphery of the oil industry are especially expat-heavy, while millions of Asians work as domestic servants and in the catering and hospitality industries.
In addition to its concerns over domestic unemployment, the Saudi government sees the expat community as a source of social insecurity.
The government is wary of importing liberal Western morals, and feels foreigners have contributed to rising crime.