Armenian Prime Minister Tigran Sargsyan sent a letter of condolence to his Russian counterpart Vladimir Putin over the Moscow subway blasts which left over 30 people dead and 70 wounded on Monday morning.

"Please accept my most profound condolences for those human lives lost in the terrorist act in Moscow subway. This tragic event testifies once again the need for inevitable and merciless retribution for such barbaric and inhumane manifestations of terrorism. At this time of hardship, I share in your sorrow for the untimely deaths and convey words of sincere sympathy to the family and relatives of the victims," the letter says.