43°23′19″N 41°09′19″E / 43.388541°N 41.155232°E / 43.388541; 41.155232Russia has a 255.4 kilometres (158.7 mi) border with a self-proclaimed, internationally unrecognized republic of Abkhazia, a breakaway region of Georgia under Russian occupation, while the border itself is guarded by FSB Border Service of Russia and State Security Service of Abkhazia.^{[1][2][3][4][5][6][7][8]} Georgia considers any attempt to demarcate a boundary between the breakaway region and Russia as illegitimate.^[9]

Particular is the Psou river that runs between the Abkhaz-Russian border which is vital for economic activity^[10] while nefarious actors use it as a smuggling route for illegal goods.^[11]

During the War in Abkhazia (1992–1993) when fighting had begun, the 221 km Abkhazian section of the railway extending from Psou roadside stop (Abkhazia–Russia border) up to Ingur roadside stop (Abkhazia-Georgia border) had been closed for Armenia and Georgia since Aug 14 1992, after the railway bridge over the River of Ingur (dividing Georgia from Abkhazia) was detonated.^[12] Later on on October 6, 1992, the Abkhaz forces captured Gagra and reached the Russian border shortly thereafter.^[13][14]

On September 19, 1994, the Russian Federation had closed its border with Abkhazia, and later on December 19, it would close the border along the Psou River.^{[15][16][17][18]}

The Russian Federation had ordered that all shipping to Sukhumi was to be closed again on January 5, 1996,^[15] which explains why an incident took place in March 1996, where a Turkish ship was prevented from entering into the port of Sukhumi.^[19]

In c. 2000, the Russian Federation had "relaxed" its border controls to "allow" men of fighting age, presumably because of the Second Chechen War.^[20]

In c. 2005, the Russian Federation unilaterally reopened the Psou-Sokhumi section for both civilian and military transport.^[21]

In 2006, the Psou-border was opened to all possessing appropriate documentation.^[22][23] In June of that year, the Russian Federation provided 200,000 tons of bitumen to assist road construction, the Sukhumi-Psou rehabilitation – at least 99 million roubles ($3.8million) was also financed by the Moscow government.^[24][25] Later in July, Russia delivered ammunition, automatic rifles, grenade launchers, bombs, and mines; that equipment was transported into Abkhazia by some thirty-five to forty military trucks that crossed the Psou River from the Russian side.^[26]

On January 24, 2011, it was reported that Russia had financed repairs on the Abkhaz Railway which would span over three months and reconstruction would cover railway sections from the River Psou on the Russian border to Sokhumi.^[27]

Notably, there was a dispute between the two parties^[which?] over a tract of land 160 square kilometres (62 sq mi)^[28] in size near the resort town of Krasnaya Polyana that flared in the lead-up to the Sochi Olympics.^{[29][30][31][32][33]} The dispute has since been dropped.^[34]

On April 8–20, 2020, then acting President of Abkhazia Valeri Bganba had signed an order to close the entire state border with Russia along the Psou River, presumably because of COVID-19 pandemic.^[35]

During the XXVII St. Petersburg International Economic Forum on June 5–8, 2024, both sides stated that they would work together in order to "simplify" border controls.^[36]