Turkey began curbing Russian imports on Monday as tensions over Georgia strained NATO'S relations with Moscow. “The goods entering Turkey from Russia are going to be subjected to additional physical searches starting Monday. Russian goods will be forced to wait at the border,” said a Turkish trade official, who spoke on condition of anonymity. Turkish exporters have been hit by delays at Russian border crossings since NATO-member Turkey allowed two US ships to transit the Bosphorus Strait to provide aid to Georgia after Moscow's military action there. “Russia started these measures and we have been forced to respond in turn,” the Turkish official said. Russia, which is Turkey's largest trade partner and supplies two thirds of its natural gas needs, has been angered by what it calls a NATO build-up in the Black Sea. Entrance to the sea is via the Turkish-controlled Bosphorus Strait. It says long inspections on trucks from Turkey are due to a new customs law, but analysts say Moscow could be flexing its economic muscle to put pressure on Ankara. Turkish business groups said exporters would lose $3 billion in the short term if the delays on goods were kept in place. Turkey, a close US ally which aspires to join the European Union, has been forced to walk a fine line between its loyalties to NATO and its large financial and energy interests in Russia. Russian Foreign Minister Sergei Lavrov is due in Istanbul on Tuesday in a visit expected to be dominated by talks over Turkey's management of shipping through the Bosphorus strait. The international community has condemned Russia's campaign in Georgia and its subsequent recognition of Georgian breakaway regions South Ossetia and Abkhazia as independent states. EU leaders meet in an extraordinary session on Monday to try to unite behind a strong response to Russia's actions in Georgia, but Moscow warned it would hit back.