The US today faced an international clamour to abolish the death penalty during a debate at the UN human rights council in Geneva.

The council is gradually reviewing the performance of all 192 UN member states. The US took its moment in the spotlight seriously, sending a high-level delegation of around 30 officials led by Esther Brimmer, the assistant secretary of state for international organisation affairs.

The delegation was given a mostly warm welcome by delegates of the 47-member council, but was forced to listen to repeated calls for the US to put an end to the death penalty.

More than 1,200 men and women have been put to death in the US since executions resumed in 1977 after a decade without them, according to Amnesty International.

Three jurisdictions – Texas, Virginia, and Oklahoma – account for more than half the country's executions. Missouri has approximately 40 people on death row, but has not executed anyone since 2005.

At the end of 2009, 139 countries had abolished the death penalty. The US finds itself grouped with authoritarian countries such as China and Iran in still executing people.

Harold Hongju Koh, the state department's legal adviser, said capital punishment was a subject of vigorous debate and litigation in the US and was applied for in only the most serious crimes.

He pointed out that there were strict procedural safeguards, adding that, in recent years, the supreme court had narrowed the list of offences for which the death penalty could be applied.

But he insisted that capital punishment did not violate international law, telling the council: "International human rights law does not bar it per se."

Koh also strongly defended the use of unmanned drone aircraft to kill "high value tagets" on the Afghanistan-Pakistan border and in Yemen.

"Our targeting practice complies with all human rights law," he said. "Operations are conducted in conformity with rule of law principles. It has been long legitimate to target enemy leaders and force is directed only at lawful targets."

Since the beginning of September, Barack Obama has authorised at least 25 targeted killings.

While the attacks have killed senior al-Qaida and Taliban figures, they have also killed civilians, including a large number of women and children, sparking anger against the US.

The fiercest criticism at the UN council came from countries at odds with the US.

The Cuban ambassador, Rodolfo Reyes Rodriguez, who spoke first, called on the Americans to end their embargo against his country.

Venezuela's envoy, Germán Mundarain Hernández, said the US should "close Guantánamo and secret detention centres around the world, punish those people who torture, disappear and execute detainees arbitrarily and provide compensation to victims".

Iran's delegation urged the US to "halt serious violations of human rights and humanitarian law including covert external operations by the CIA carried out on pretext of combating terrorism".

Koh said the Obama administration had begun by "turning the page" on Bush-era practices and fully ensured the humane treatment of detainees.

"Let there be no doubt, the United States does not torture and it will not torture," he declared.

A state department submission in August, written after extensive public consultation, said the US was "currently at war with al-Qaida and its associated forces" but that it would comply with all applicable domestic and international law in armed conflicts and had ordered foreign detainees be treated humanely.

The report said the US was a democracy guided by "simple but powerful principles", but admits to discrimination against black people and Hispanics and a "broken" immigration system.