"Despite all the pressure from our enemies, we will pursue our policy of detente, but we also insist on becoming stronger -- militarily, politically and economically," the reformist president said in a speech at a military parade marking the anniversary of the outbreak of the 1980-88 war with Iraq.
"We are opposed to the spread of weapons of mass destruction and the very existence of atomic weapons," said Khatami, whose country has been slapped with a deadline from the UN's International Atomic Energy Agency (IAEA) to account for its suspect civil nuclear programme.
Khatami echoed widespread anger here over the IAEA's October 31 deadline, contained in a resolution passed on September 12 that calls on Iran to answer all the agency's questions regarding its enrichment activities, provide unrestricted access to UN inspectors and a detailed list of its nuclear-related imports.
Many officials here have presented the resolution as an effort to scupper the development of civil nuclear technology.
"We will not renounce our right to become stronger in the domains of science and technology," Khatami told the crowd gathered for the start of "Sacred Defence Week" -- a week of events marking the bloody conflict with Saddam Hussein.
"The Iranian people, who are pacifists and have a love of justice, have always said their military strategy was defensive and that they do not want weapons of mass destruction. Yet it is they who are subject to international pressure by those who support Israel -- the centre of terrorism and weapons of mass destruction," the president said.
"It is the Zionist regime which possesses a considerable atomic arsenal and uses the worst forms of terrorism in Palestine while we are partisans of peace, stability and a region free of atomic weapons," he added.