The move removes a legal loophole that had developed, and the decree has been posted on Russia's official legal registry.
In 2008 Putin signed a previous decree saying all non-citizens of Estonia and Latvia who were formerly Soviet citizens, plus their under-age children had the right to enter Russia without a visa.
But in 2016 Latvian non-citizen Oksana Karaja, a student in Moscow, was deported because she had no visa. the new decree includes in the visa-free regime non-citizens born after 6 February 1992 and who have reached adulthood.
The presidential decree is effective immediately.
There remain around 250,000 non-citizens in Latvia and around 80,000 in Estonia. These are mainly Soviet-era immigrants to the countries and their descendants who have chosen not to undergo naturalization during the last two decades.
However, the new decree will affect only around 6,000 people in total, according to earlier information from the Russian Ministry of Foreign Affairs.
