"If we don’t reach a final agreement in the negotiations by the end of July, the conditions will never return to the past and even if the US and the Group 5+1 (the US, Russia, China, Britain and France plus Germany) gather (to stand against us in one front), the conditions of the past will never happen again," Rouhani said in a press conference in Tehran on Saturday.
"Since the very first days of this government, we have displayed in the negotiations that the government is completely ready for the negotiations and believes that the nuclear issue can merely be settled through negotiations," he added.
Rouhani underscored that if the westerners enter the talks with good will and serious determination, "the nuclear issue can be settled within (the remaining) five weeks (until the deadline of July 20 envisaged in the Geneva agreement in November) and we can reach the final agreement".
He said but if the negotiations fail, the world public opinion will blame the US radicals for blocking the agreement and not the Islamic Republic of Iran, which has sought the settlement of the issue.
Rouhani added that at present Tehran enjoys good economic relations with different world states since the sanctions system has cracked.
Rouhani referred to the remaining differences, some of them fundamental, between Iran and the G5+1, but said, "There is no difference over two issues."
"The first issue is that Iran will continue enrichment and there is no debate in this regard; the second issue is that if an agreement is reached, (all) the sanctions should be removed since one of the paragraphs of the final agreement will pertain to the full removal of the sanctions."
He, meantime, said that if no agreement is reached, "we won't have much problem", advising the West to "take this best opportunity" to settle its differences with Tehran.
His remarks came as the fifth round of negotiations between Iran and the Group 5+1 is due to take place in Vienna on June 16 to 20.
Iranian Foreign Minister and Head of the country's negotiating team in nuclear talks with the world powers Mohammad Javad Zarif is due to meet EU foreign policy chief Catherine Ashton in Vienna on Monday noon.
Zarif and Ashton have decided to meet each other for a luncheon at Iran's office at the International Atomic Energy Agency (IAEA) headquarters in Vienna on Monday to discuss the latest developments in the talks between Tehran and the six world powers.
They will then decide if they should start the multilateral negotiations among the seven nations on Monday or Tuesday.
A senior Iranian delegation headed by two of Zarif's deputies, Seyed Abbas Araqchi and Majid Takht Ravanchi, held separate bilateral meetings with most members of the G5+1 in Geneva and Rome earlier this week.
On Monday afternoon, representatives from Iran, EU and the United States had five hours of trilateral talks, followed by a bilateral meeting between the Iranian and American delegations in Geneva on Tuesday.
Araqchi held "specially important" talks with his Russian counterpart Sergei Ryabkov at Rome Airport on Wednesday night.
The Iranian team also held bilateral talks with the French negotiators in Geneva on Wednesday.
Araqchi said the Iranian and French teams of negotiators had over 3 hours of useful talks in a positive atmosphere.
"These talks on the threshold of the upcoming Vienna negotiations were useful," Araqchi told FNA on Wednesday.
He said that the two sides discussed issues related to the nuclear talks as Iran and the Group 5+1 are preparing for the next round of talks in the Austrian capital.
The French foreign ministry's new political director Nicolas de Rivière, who has replaced the longtime lead negotiator and political director Jacques Audibert, was leading France's negotiating team in the Wednesday meeting.
Meantime, the German's top envoy to the Iran-Group 5+1 talks Hans Deiter Lucas arrived in Tehran on Friday to meet his Iranian counterparts.
In November 2013, Iran and the world powers signed an interim nuclear deal in the Swiss city of Geneva that came into force on January 20. The deadline for attaining a final deal is July 20.
Iran and the six world powers last met in their fourth round of talks in Vienna on May 14-16. Since the November deal, the seven nations have been discussing ways to iron out differences and start drafting a final deal that would end the West’s dispute with Iran over the country’s nuclear energy program.
After the May meeting, Iran said there has been no tangible progress in writing the draft text of the agreement and it blamed the US for the failure, saying Washington has made excessive demands beyond the agreements made in the previous rounds of talks.
