There were angry protests in the Latvian capital of Riga as politicians gathered to finalise a border agreement with Russia. The deal had been delayed for four years due to an ongoing land dispute. It was finally ratified when Riga dropped its claim to a small slice of Russian territory which was part of pre-second World War Latvia.
Russian Foreign Minister Sergei Lavrov told his Latvian counterpart Maris Reikstins that more work must be done to help minorities.
Russia has been angered by what it sees as Latvian discrimination against its large Russian-speaking population, many of whom were denied citizenship after the small Baltic state regained its independence in 1991.
Latvia has in turn remained suspicious of Moscow, which has dominated the region historically. But experts say confidence has grown since it joined NATO and the EU in 2004.