"The performance of the US and Britain over the past three years at the [United Nations] Security Council has been unconstructive and in line with giving legitimacy to the aggressors against Yemen," Qassemi said on Tuesday.
He added that Washington and London have been using the mechanisms of the UN Security Council over the past three years to cover up "war crimes" committed by Saudi Arabia and its allies in the impoverished country.
The Iranian spokesman made the comment a day after Russia vetoed a resolution at the Security Council, presented by Britain and strongly backed by the United States, that called for "additional measures" against Iran over accusations that it violated the 2015 arms embargo on the war-torn Arabian Peninsula state.
The draft resolution gained 11 favorable votes at the 15-member Security Council but was blocked by Russia's veto. China and Kazakhstan abstained, while Bolivia also voted against the measure.
A group of so-called independent United Nations experts monitoring the sanctions on Yemen reported to the Security Council in January that it had “identified missile remnants, related military equipment and military unmanned aerial vehicles that are of Iranian origin and were brought into Yemen after the imposition of the targeted arms embargo.”
The Security Council instead adopted unanimously a Russian-written resolution that called for a one-year extension of sanctions against Yemen and a renewal of the work of the panel of experts.
In reaction to Western efforts to target Iran over the allegations of providing arms to Yemen's Houthis, Qassemi said, "As had been expected, the UK-proposed resolution had no outcome for its sponsors due to its unrealistic [nature] and led to another defeat, particularly for the United States of America, on the international scene and at the United Nations."
Iranian Deputy Foreign Minister for Political Affairs Abbas Araqchi said on Tuesday that Russia's vote against the UN draft resolution represented another setback for the US.
"Based on a one-sided report, they intended to pass a resolution that also referred to Iran, but they failed," Araqchi said, adding, "This is yet another failure by the US government to drag Iran to the Security Council."
Elsewhere in his comments, the Iranian Foreign Ministry spokesperson expressed deep concern over the continued warmongering policies and relentless attacks on the oppressed Yemeni people and called on the international community to take a decisive action to stop foreign aggression and killing of thousands of innocent people in Yemen.
Qassemi said all those who are playing a destructive role by selling modern arms to boost the aggressive countries weapons stockpiles, escalating the Yemeni crisis and destabilizing the Middle East region, are responsible for any harm coming to the women and children of Yemen.
He warned that Yemen is suffering from a humanitarian catastrophe due to a devastating war and sanctions.
He said the US, Britain and France, who had been the sponsors and supporters of the vetoed resolution, were sending out the wrong signals and evading accountability.
Qassemi said these countries are the main suppliers of lethal weapons and are playing a prominent role in Saudi Arabia's warmongering and ongoing military aggression against Yemen.
Since March 2015, the Saudi regime, together with a coalition of its allies, has been heavily bombarding Yemen as part of a brutal campaign against its impoverished southern neighbor. It has been attempting unsuccessfully to reinstall Yemen’s former president Abd Rabbuh Mansur Hadi, a staunch ally of Riyadh.
The Saudi campaign has killed at least 13,600 people since its onset. Furthermore, much of the country’s infrastructure, including hospitals, schools, and factories, has been reduced to rubble in the Saudi war.
A blockade imposed by the Saudi-led coalition on Yemen has also caused widespread famine in the already-impoverished country.