Bahrain's interior ministry said on Tuesday that it would stop issuing new visas to Qatari nationals, escalating measures against Qatar more than a year into a diplomatic row.
The statement, carried on state news agency BNA, said Qatari students studying in the kingdom and other Qatari citizens with existing visas would not be affected.
It also said the move came in response "hostile acts" by Qatari authorities. It did not elaborate.
Bahrain, Saudi Arabia, the United Arab Emirates and Egypt cut diplomatic, transport and trade ties with Qatar in June 2017, accusing it of financing terrorism. Doha denies that and says the boycott is an attempt to rein in its support for reform.
In October, Bahrain said it would impose entry visas on Qatari nationals as a security measure.
Citizens from the six-nation Gulf Cooperation Council countries are otherwise supposed to be able to travel within the GCC carrying only an identity card.