Iran unveiled on Saturday domestically-produced deuterated compounds at Arak heavy water plant and called on the five permanent members of UN Security Council plus Germany (G5+1) to seize the time in the forthcoming nuclear talks in Istanbul.

Acting Iranian Foreign Minister and Head of the Atomic Energy Organization of Iran (AEOI) Ali Akabar Salehi on Saturday hailed the domestically-produced deuterated compounds at Arak heavy water plant and the achievement for its use in medical research.

Iran has become self-sufficient in deuterated compounds at Arak heavy water facility, the local satellite Press TV quoted an Iranian scientist as saying.

In a meeting with the delegates from Algeria, Cuba, Syria, Oman, Egypt, Venezuela, and the Arab League who arrived in Iran on Saturday for a tour to Iran's nuclear sites, Salehi described Iran 's move as a gesture of "goodwill and transparency," Press TV said.

Iran's invitation to its nuclear sites is its last trust-building step, Salehi told local ISNA news agency.

"No country in the world will choose to show its nuclear facilities to others and Iran's invitation reiterates peaceful nature of its nuclear work, Salehi was quoted as saying by ISNA.

The Iranian official called on G5+1 to seize the opportunity in the next round of talks in Istanbul.

Meanwhile, Salehi said Saturday that 40-megawatt Arak heavy water research reactor in central Iran will be commissioned within the next two to three years, according to the official IRNA news agency.

Speaking to the reporters in Arak on the sidelines of the tour to the plant, Salehi said Arak reactor is to meet the country's demands for radio isotopes and possible extra output will be exported abroad, according to IRNA.

He said once again that Iran renounces the production and the use of Weapons of Mass Destruction (WMDs), according to the report.

On Jan 4, the media reported that Iran had invited ambassadors of Russia, China, the European Union and its allies among the Arab and the developing world to visit its nuclear sites ahead of the Istanbul talks slated for late January on Iran's nuclear issues between world major powers and Tehran.

The EU foreign affairs chief Catherine Ashton, however, turned down Tehran's invitation, saying that it was IAEA's function to inspect the Iranian nuclear facilities. Several other invited countries also refused to visit nuclear sites of Iran.

The US Treasury Department on Thursday imposed sanctions on 24 shipping companies affiliated with the Islamic Republic of Iran Shipping Lines (IRISL) and two entities that are subordinates of Iran's Aerospace Industries Organization (AIO).

"Today's actions build on Treasury's efforts to expose the financial and corporate underpinnings of IRISL and AIO, two entities that face international sanctions for their involvement in Iran's missile programs," the US Treasury Department said in a statement.

This is the latest round of financial sanctions taken by the United States to isolate Iran from the international financial system.

According to earlier reports, the United States and the European Union prepared to impose a new round of sanctions against Iran this year over Tehran's refusal to halt its controversial nuclear program.

The West has long accused Iran of secretly developing nuclear weapons under civilian disguise, although Tehran has always denied such charges.