The remarks by Iraq's top diplomat reflect the country's fears that the Syrian conflict may be threatening its fragile domestic security, as well as growing international concerns about the dangers posed by foreign militants waging a foreign-backed war against the Syrian government.

Speaking at a security conference in Bahrain on Saturday, Zebari further said, "The most important danger coming out of the Syria conflict for Iraq...and for the region is the mushrooming of terrorist groups and fronts in Syria,"

He added "These are armies of recruits. They're not all Syrians. There are European nationals. Some of them have come as far as from Australia, from Canada, and from many other countries. This is really toxic."

According to reports, some 1,200-1,700 Europeans are fighting along with militants in Syria against the government of President Bashar al-Assad. Thousands others militants are also thought to come from Arab and other countries.

The Iraqi arm of al-Qaeda group has also joined the conflict in Syria and moved into militant-held areas in north of the country.

More than 8,000 people have been killed in bombings and shootings in Iraq since the beginning of 2013. The violence is widely blamed on al-Qaeda militants and is believed to be part of their cross-border ambitions.

Syria has been gripped by deadly unrest since March 2011. A recent British defense study showed that about 100,000 militants, fragmented into 1,000 groups, are fighting in Syria against the government and people.

RA/MB