US President Donald Trump's administration has been taking a harder line with the United Nations to extend and strengthen the embargo on Iran, warning that its lifting would let Tehran acquire weapons that could fuel conflicts in the Middle East.
"Americans are already angry, upset, and wanting to take this issue to the Security Council. We want four permanent members of the (UN Security) Council to stand up to America," Iranian President Hassan Rouhani said in a televised speech.
"Particularly, we expect Russia and China to resist this US plot. America will not succeed ... and we will increase our defense capabilities as we have been doing so even under sanctions."
Tehran and its rival Saudi Arabia, a close US ally, have been involved in proxy wars and political confrontations in the region for decades, from Iraq and Syria to Bahrain and Yemen.
Council veto-powers Russia and China have already signaled they are against re-imposing an arms embargo on Iran.