Iran plans to host a meeting of regional and other countries that have "realistic stances" on Syria later this week to find ways to resolve the country's crisis, the official IRNA news agency reported on Monday.

"A consultation meeting on Syria will be held in Tehran on Thursday with the participation of those countries who have realistic stances on this country," IRNA quoted Deputy Foreign Minister Hossein Amir-Abdollahian as saying on Monday.

The aim of the meeting is to find "ways out of the current crisis, the return of stability and calm to that country and also supporting all constructive regional and international efforts," Abdollahian said.

The report did not say which countries were invited to the meeting but, because of their involvement in the Syrian crisis, any meeting held without Saudi Arabia, Qatar and Turkey is unlikely to have any significant result.

Shi'ite Muslim Iran has steadfastly supported Syrian President Bashar Assad in his struggle to crush the 17-month-old rebellion against his rule, although it had backed other popular uprisings which removed leaders in Egypt, Libya and Yemen.

Iranian leaders have accused the West of plotting with Arab countries to overthrow the Syrian leadership and bolster the status of Israel in the region by backing extremist militant groups.

Last month, Iran said it was ready to host talks between the Syrian government and opposition groups, an offer rejected by members of the Syrian opposition.

Iranian currency sinks

Meanwhile, Iran's rial sank about 5 percent in trading against the U.S. dollar on Monday after the central bank said it would change the currency's official exchange rate, prompting fears of another devaluation.

The rial was trading in the free market at around 21,510 per dollar, according to Persian-language currency tracking website Mazanex, down from about 20,440 on Sunday.

Central bank governor Mahmoud Bahmani said on Sunday he would announce a change to the government's "reference rate" of 12,260 rials to the dollar "within the next 10 days", Iranian media reported.

Iranian media speculated that the new reference rate might be between 15,000 and 16,000 rials.

Most Iranians are unable to obtain dollars at the official rate and must instead use the free market, which is much more expensive.

The drop in currency comes days after the Washington Post reported that the chief commander of Iran’s elite Revolutionary Guard said that the biggest threat to his country is a “soft war” launched by enemies to force the Islamic Republic to give up its nuclear program.

In comments posted on the Guard’s website, Gen. Mohammad Ali Jafari said Iran is in a “sensitive and fateful period” in its history. He did not define the term “soft war,” but it likely implies non-military measures like economic sanctions, espionage and attacks on computer networks.