Russia's defence industry has exported $6.5 billion worth of arms in the first half of 2012, an increase of 14 percent year-on-year, President Vladimir Putin said Monday.

The country's foreign arms sales, which have grown steadily over the recent years, have faced increased scrutiny recently as the West and the Arab League demand that it halts military cooperation with Bashar al-Assad's regime in Syria, amid the conflict that has claimed over 15,000 lives.

Officials however have defended Russia's contract responsibilities and Putin noted Monday that Russia "always carries out all of the obligations it undertakes," though without specifically mentioning Syria.

"Export sales of Russia's defence industry has already surpassed $6.5 billion," he said in televised remarks, adding that arms sales have doubled in the last two years and grew 14 percent since the first six months of 2011.

"This year, new export contracts worth $5.7 billion have been signed, that is $2.4 billion more than in the first half of 2011," he said at a meeting.

Putin added that arms trade is an "effective instrument of promoting our national interests, both political and economic." Russia sells arms to a total of 55 countries, he said.

Russia, the second largest arms exporter after the United States, made deals worth a record $13.2 billion in 2011 despite taking a loss of about $4 billion due to the regime change in Libya, a partner since Soviet times.

It has been heavily criticised for attempting to deliver Mi-25 attack helicopters to Syria in a shipment that was held up when the British insurer of the vessel dropped cover.

Russia has defended the delivery, arguing that the helicopters have been purchased by Damascus years ago and were undergoing planned repairs on Russian soil.