Estonian citizens are being advised against non-urgent travel to Russia, to totally avoid Russian-Ukrainian border areas and to return to Estonia if possible.
The Estonian Ministry of Foreign Affairs issued the updated travel advice on Tuesday due to increased "military activity" in Russia.
"People with both Estonian and Russian citizenship must keep in mind that on Russian territory, they are considered Russian citizens by the Russian Federation and Estonia's options for providing consular assistance are limited," a statement said.
The ministry urged Estonian citizens temporarily in Russia to register their stay on their website.
It reminded citizens that consular assistance is only available in the Estonian Embassy in Moscow.
"Assistance in other cases (especially if the person in need is not in Moscow) is extremely difficult and time-consuming," the ministry wrote.
Estonia also advised citizens not to travel to Russia after the start of the full-scale invasion in February.
Editor: Helen Wright