The Presidium of the Supreme Soviet of the Union of Soviet Socialist Republics and the President of the Republic of Finland,
The Treaty of friendship, coöperation and mutual assistance of 6 April 1948 between the Union of Soviet Socialist Republics and the Republic of Finland shall remain in force for a period of 20 years from the date of the entry into force of this Protocol.
If neither of the High Contracting Parties denounces the Treaty one year before the expiry of the said period, it shall remain in force for further periods of five years until such time as one of the High Contracting Parties gives notice in writing, one year before the expiry of the current five-year period, of its intention to terminate the Treaty.
This Protocol is subject to ratification and shall enter into force on the date of the exchange of the instruments of ratification, which shall take place at Helsinki as soon as possible.
In witness whereof, the plenipotentiaries have signed this Protocol and have thereto affixed their seals.
Done at Moscow on 20 July 1970, in duplicate in the Russian and Finnish languages, both texts being equally authentic.