Washington: Harvard University has advised international students to return to the United States before September 15, ahead of the implementation of changes to US visa regulations.

The US government has introduced significant changes to visa rules governing international students, including Indians, pursuing higher education in the country.

Under the existing system, students holding F-1 visas are admitted under the 'duration of status' provision, allowing them to remain in the US for the duration of their academic programme.

Under the new rules, students entering the US after September 15 will be granted F-1 status for a maximum period of four years. The grace period available after completion of studies for returning to their home country will also be reduced from 60 days to 30 days.

Students requiring additional time would have to apply separately for an extension, according to the information cited by Harvard.

The university has advised international students to return before the new rules take effect. Students already in the US when the changes come into force may be covered by transitional arrangements, while those travelling abroad and returning after September 15 could face different admission procedures.