Syria said on Tuesday the attacks in Brussels were the "inevitable result of wrong policies and a tolerance for terrorism", and called for an international effort to confront the phenomenon.
A foreign ministry source, quoted by state news agency SANA, also said the attacks were the consequence of some countries"describing terrorist groups as moderate".
The Syrian government says all armed groups fighting to topple President Bashar al-Assad are terrorists. Assad's Western opponents have designated Islamic State and the Nusra Front as terrorist groups, but say many Syrian rebels belong to moderate factions.
"Syria, which has confronted takfiri terrorism for five years renews its call to combine all sincere international efforts to confront the danger of terrorism," SANA quoted the ministry source as saying.