Ban Ki-moon, the UN secretary-general, will attend a summit of the Non-Aligned Movement in Tehran next week, defying calls from the United States and Israel to boycott the event, the UN has confirmed.

“With respect to the Islamic Republic of Iran, the secretary-general will use the opportunity to convey the clear concerns and expectations of the international community,” UN spokesperson Martin Nesirky said on Wednesday.

“These include Iran’s nuclear programme, terrorism, human rights and the crisis in Syria.”

He said Ban is “fully aware of the sensitivities” of the visit, but not going “would be a missed opportunity”.

Ban will be in Tehran from August 29 to 31.

‘Horrible mistake’

“The secretary-general looks forward to the summit as an opportunity to work with the participating heads of state and government, including the host country, towards solutions on issues that are central to the global agenda including follow-up to the Rio+20 conference on sustainable development, disarmament, conflict prevention and support for countries in transition,” Nesirky said.

The Non-Aligned Movement began in 1961 in Belgrade at the height of the Cold War by countries that considered themselves outside of the major power blocs led at the time by the Soviet Union and US.

Since then, the movement has grown and Iran was elected as NAM’s current chair, replacing Egypt.

Binyamin Netanyahu, the Israeli prime minister, has reportedly called Ban himself to warn him that attending the summit would be a “horrible mistake”.

Victoria Nuland, the US state department spokesperson, last week said that Ban’s participation in the Tehran summit would “not send a good signal”.

After the announcement that Ban would go, she called on the secretary-general to “say directly to Iran’s leaders what the international community’s concerns are” and to attempt to get Iran to “come clean on their nuclear programme and to solve this particular issue diplomatically”.