The bomb that brought down the Russian Airbus A321 over Egypt last month, killing all 224 people on board, may have been revenge for Russia's involvement in the anti-Islamic State campaign in Syria, the head of the Foreign Ministry's department of new challenges and threats said.

"It may well have been retribution for our participation in the fight against IS," Ilya Rogachyov was quoted as saying in an interview with the Kommersant newspaper, published Friday.

He added that he considered stepping up Russia's bombing campaign “the only appropriate response” to the attack, describing IS as "a cancer gripping half of Syria and nearly half of Iraq."

"I have no doubt that the terror threat [to Russia] will only become more serious if we don't do anything. Are we supposed to wait until IS fighters knock on our door?" he said.

On Tuesday, Russia's Federal Security Service officially confirmed that a terror act was to blame for the A321 crash. Islamic State, which is banned in Russia as a terrorist organization, has claimed responsibility.