In observance of the 20th anniversary of the 1989 Baltic Way demonstration, the prime ministers of Estonia, Latvia and Lithuania have signed a joint declaration supporting a call to make Aug. 23 a European day of commemoration for victims of both Stalinism and Nazism.

Meeting in Vilnius, Estonian Prime Minister Andrus Ansips, Latvian Prime Minister Valdis Dombrovskis and Lithuanian Prime Minister Andrius Kubilius put their names to the declaration that also notes the renewal of their countries’ independence in 1991 led to a new era of cooperation between the Baltic states, according to a press release from Latvia’s Cabinet of Ministers. The leaders pledged to strengthen their ties with the European Union and the NATO defense alliance.

“Estonia, Latvia and Lithuania will continue to jointly work to preserve historic memory and for the honest and open awareness of totalitarian heritage in 20th century Europe,” according to the Aug. 23 declaration.

On Aug. 23, 1939, the Soviet Union and Nazi Germany signed a non-aggression treaty called the Molotov-Ribbentrop Pact. The treaty included secret protocols that led to the Soviet occupation of the Baltic republics. The Baltic Way demonstration, in which an estimated 2 million people linked hands in a human chain spanning Estonia, Latvia and Lithuania, was a protest organized on the 50th anniversary of the pact.

The European Parliament has adopted a resolution calling for the establishment of a European Day of Remembrance for Victims of Stalinism and Nazism “in order to preserve the memory of the victims of mass deportations and exterminations, and at the same time rooting democracy more firmly and reinforcing peace and stability in our continent.”

The Parliamentary Assembly of the Organization for Security and Co-operation in Europe (OSCE), in a July meeting in Lithuania, adopted a resolution that equated Stalinism with Nazism and gave its support to setting aside Aug. 23 as a day of commemoration.

Russian officials reacted negatively, walking out of the meeting. The Russian Foreign Ministry and the State Duma called the OSCE resolution insulting.