"Those who speak about sanctions would be damaged more (than Iran)," Mahmoud Ahmadinejad told a news conference on Monday.
"But no particular event will happen, don't worry."
In wide-ranging remarks, Ahmadinejad maintained his opposition to Israel, calling it an artificial state that could not continue to exist.
Ahmadinejad said Iran would reconsider its compliance with NPT and membership of the International Atomic Energy Agency if they continued to be of no benefit to the country.
"What has more than 30 years of membership in the agency given us?" he asked.
The agency, a UN body, has accused Iran of failing to answer questions about its nuclear programme and reported the country to the Security Council for non-compliance.
The Security Council has given Iran until Friday to suspend enrichment of uranium, a process that can produce fuel for nuclear reactors material for nuclear warheads.
Iran has rejected the demand, arguing it is entitled to the peaceful use of enrichment as a signatory to the NPT.
Iran has until Friday to suspend
enrichment of uranium
"Working in the framework of the Nuclear Nonproliferation Treaty and the agency is our concrete policy," he added.
"(But) if we see that they are violating our rights, or they don't want to accept (our rights), well, we will reconsider."
The president also questioned the need for talks with the United States about neighboring Iraq.
US and Iraq
In March, the United States said it was ready for talks with Iran about its help with quelling the chaos in Iraq, where a Shia Muslim majority with close ties to Tehran has a majority share in the government.
"Many times they (Americans) sent messages asking for help on security in Iraq. Iraqi leaders also asked the same. Unfortunately they did not have a good attitude in this regard. We believe that with the formation of new government, there is no need," Ahmadinejad said.
The Iranian president has long campaigned against Israel, saying in October that the Jewish state should be "wiped off the map."
He has said Europe should find a home for Israelis, who should not live on Palestinian land.
"Some 60 years has passed since the end of World War II. Why should the people of Germany and Palestine pay now for a war in which the current generation was not involved?" Ahmadinejad asked.
"We say that this fake regime (Israel) cannot logically continue to live. Open the doors (of Europe) and let the Jews go back to their own countries"
president of Iran
"We say that this fake regime (Israel) cannot logically continue to live," he said.
"Open the doors (of Europe) and let the Jews go back to their own countries," the president said.
He added that Europeans should jettison their "anti-Semitism" to enable Israelis to "return" to their continent, and "allow Palestinians to decide their own fate and live freely."