Iranian President Hassan Rouhani has criticized the United States for "imposing its policies on the rest of the world".
Speaking at an international summit in the Chinese city of Qingdao on Sunday, Rouhani said the US' withdrawal from the Iran nuclear deal poses a potential threat to the world.
"The recent example of such unilateralism and the defiance of the decisions of the international community by the US government is its withdrawal from the JCPOA (Joint Comprehensive Plan of Action, the formal name of the nuclear deal)," Rouhani said during the meeting of the Shanghai Cooperation Organisation (SCO), a regional security pact in which Iran has observer status.
US President Donald Trump pulled Washington out of the 2015 international pact with Iran that placed limits on its nuclear program in return for the easing of economic sanctions.
Rouhani praised China and Russia for their continued efforts to maintain the nuclear deal.
Russian President Vladimir Putin also criticized the US for its withdrawal, claiming the decision could potentially destabilize the situation.
Putin said Russia will honor its part of the deal, adding Moscow is still in favor of the "unconditional implementation" of the pact.
The remarks were made during the 18th annual summit of SCO, an eight-member grouping led by Beijing and Moscow - in the coastal city of Qingdao.
The JCPOA was officially not on the agenda for the SCO, which aims to increase regional security and stability through trade, investment and development cooperation.
The two-day event was opened on Saturday by Chinese leader Xi Jinping.
The SCO summit was stand in stark contrast to Saturday's G7 meeting, held in Canada over the weekend.
That summit, attended by the US, Canada, France, Germany, Italy, Japan, the UK and the European Union, tensions rose high after US President Donald Trump pulled out of a joint statement, citing "false statements" by Canadian Prime Minister Justin Trudeau.
The summit was also marked by the looming trade dispute between the US and several other countries as a result of Trump imposing tariffs on steel and aluminum imports into the US from Canada, Mexico and European Union countries.