The Trump administration has proposed a new rule to limit to four years the period of stay for non-immigrant international students and foreign media representatives.

It plans to cut the duration further to two years for those from certain countries under the F, J and I category visas, used for students, exchange visitors and media representatives, respectively.

Foreigners on these visas can currently stay for “duration of status”, or the period of course in case of students, and employment in case of media representatives. This applies also to the dependents of principal visa holders.

The proposed rule, published by the department of homeland security, will be open for comments for 30 days. But it was not clear when it will go into effect. President Donald Trump has only a few months to finalise the rule by January 2021, and longer if he is re-elected.

If he loses the November 3 election to Joe Biden, the Democrat will be under no obligation to implement it.

The duration of stay can be extended either by filing for extension with the US Citizenship and Immigration Services (USCIS) or by going back to their countries of origin for fresh visas.

The two-year rule will apply to people from countries that are either on state department’s list of state sponsors of terrorism or who have an overstay rate of over 10%.

“The significant increase in the volume of F academic students, J exchange visitors, and I foreign information media representatives poses a challenge to the Department’s ability to monitor and oversee these categories of non-immigrants while they are in the United States,” the notice said.

The department added it is “concerned about the integrity of the programmes and a potential for increased risk to national security” from people on these visas.

There are an estimated 200,000 Indian students in the US, which has admitted an estimated 1 million international students every year. Together, they have generated around $41 billion’s worth of economic activity and supported 450,000 jobs, according to the American Council on Education, which represents US colleges and universities. Incomes generated from foreign students are critical to the financial health of many US colleges.