"Iran is considered as an undeniable partner in regional issues and an important partner in future prospects for the region and in resolving the problems in Iraq, Afghanistan and the Middle East," de Rio stressed in a meeting with Iranian Deputy Foreign Minister for European Affairs Ali Ahani in Tehran on Tuesday.
During the meeting she also pointed to Iran's nuclear case, and expressed the hope that the issue would be resolved through an understanding of the two sides.
"Undoubtedly, Iran is entitled to the right to enjoy civilian nuclear technology but the two sides are necessitated to build mutual confidence," she added.
Ahani, for his part, briefed de Rio on Iran's stances and policies on regional issues, and voiced Tehran's preparedness to help to their settlement, underlining that countries are required to enhance mutual cooperation to maintain security and development.
Iran and the West are at loggerheads over Tehran's nuclear program. Iran says its nuclear program is a peaceful drive to produce electricity so that the world's fourth-largest crude exporter can sell more of its oil and gas abroad and provide power to the growing number of Iranian population, whose fossil fuel would eventually run dry.
The US and its western allies allege that Iran is pursuing a nuclear weapons program while they have never presented corroborative evidence to substantiate their allegations against the Islamic Republic.
Analysts believe that the US's opposition with Iran is mainly due to the independent and home-grown nature of Tehran's nuclear technology, which gives the Islamic Republic the potential to turn into a world power and a role model for other third-world countries. Washington has laid much pressure on Iran to make it give up the most sensitive and advanced part of the technology, which is uranium enrichment, a process used for producing nuclear fuel for power plants.
Iran is under three rounds of UN Security Council sanctions for turning down West's calls to give up its right of uranium enrichment, saying the demand is politically tainted and illogical.
A fourth UNSC sanctions resolution ratified last year did not bring any fresh sanctions against Tehran and just reiterated the council's previous measures against the Islamic Republic.
Tehran has thus far ruled out halting or limiting its nuclear work in exchange for trade and other incentives, saying that renouncing its rights under the NPT would encourage world powers to put further pressure on the country and would not lead to a change in the West's hardline stance on Tehran.
Iran has also insisted that it would continue enriching uranium because it needs to provide fuel to a 300-megawatt light-water reactor it is building in the southwestern town of Darkhoveyn as well as its first nuclear power plant in the southern port city of Bushehr.