By Emma Farge

GENEVA, March 16 (Reuters) - The head of a U.N. investigation said on Monday that an Israeli air strike on a prison last year was a war crime, and warned of risks of further repression following the current U.S.-Israeli bombings.

More than 70 people were killed when Israel struck Tehran's Evin prison last June during an air war with Iran, Iranian authorities have said. The jail, known for holding political prisoners, has also been damaged in the latest U.S.-Israeli air strikes, raising fears for the detainees, who include a British couple.

By Tim Cocks

JOHANNSESBURG, March 16 (Reuters) - South Africa has no reason to cut ties with Iran, its director general of foreign affairs said, after the new U.S. ambassador was quoted as saying the country's association with the Islamic Republic was an impediment to good relations with Washington.

Iran vowed at the United Nations on Monday that it would not submit to "lawless aggression", saying 90 million citizens were in "grave danger" from US and Israeli strikes.

At the UN Human Rights Council in Geneva, where countries were discussing the rights situation in Iran, UN experts highlighted Tehran's deadly crackdown on protesters in recent months and warned that repression would likely worsen amid the Middle East war.

By Saurabh Sharma and Krishna N. Das

NEW DELHI, March 16 (Reuters) - Iran has asked India to release three tankers seized in February as part of talks seeking the safe passage of Indian‑flagged or India‑bound vessels out of the Gulf via the Strait of Hormuz, three sources with knowledge of the matter told Reuters.

Indian authorities seized the three Iran‑linked tankers near Indian waters alleging they had concealed or altered their identities and were involved in illegal ship‑to‑ship transfers at sea.

MADRID, March 16 (Reuters) - Spain will not take part in any military mission in the Strait of Hormuz because it considers the U.S.-Israeli war on Iran to be illegal, Madrid's defence and foreign affairs ministers said on Monday.

The leftist coalition government led by Prime Minister Pedro Sanchez has criticised the offensive and banned participating U.S. aircraft from using jointly operated bases in southern Spain.

School counsellor Tair Momo took a deep breath as she stared out over the vast silence of the Negev desert in southern Israel.

"I came here to get some respite, to not hear the sirens, not hear the alerts, to be in a place of nature that feels more relaxed," the 33-year-old told AFP.

As air raid sirens blare out warnings of Iranian missiles or Hezbollah rockets across much of Israel, residents of bigger towns and cities have packed out the small desert resort of Mitzpe Ramon in search of calm.

WASHINGTON, March 16 (Reuters) - The United States is "fine" with some Iranian, Indian and Chinese ships going through the Strait of Hormuz for now, Treasury Secretary Scott Bessent said on Monday, adding that any action to mitigate higher prices would depend on how long the Iran war lasts.

"We are seeing more and more of the fuel ships start to go through. The Iranian ships have been getting out already, and we've let that happen to supply the rest of the world. We've seen Indian ships go out now ... we believe some Chinese ships have gone out," he told CNBC in an interview.

WASHINGTON, March 16 (Reuters) - It remains to be seen if U.S. President Donald Trump's meeting with Chinese President Xi Jinping takes place as scheduled later this month, but any changes would be due to logistics amid the Iran war, U.S. Treasury Secretary Scott Bessent told CNBC on Monday.

Bessent's remarks come after Trump told the Financial Times on Sunday he may postpone a meeting with Xi if China does not help to unblock the Strait. The Chinese foreign ministry did not immediately respond to a Reuters request for comment.

By Joshua McElwee

VATICAN CITY, March 16 (Reuters) - Pope Leo urged journalists on Monday to highlight the suffering caused by war, cautioning against news reports that risk sliding into propaganda by glorifying conflicts or serving as "a megaphone" to amplify the voices of those in power.

In a meeting with broadcasters from Italy's TG2 television news programme, the pope made a direct appeal for reporters "to show the face of war and tell it through the eyes of the victims, so as not to turn it into a video game."

By Nidal al-Mughrabi and Rami Ayyub

CAIRO/JERUSALEM, March 16 (Reuters) - Envoys from U.S. President Donald Trump's "Board of Peace" have met representatives of Hamas in Cairo in an effort to safeguard the Gaza ceasefire, under serious strain since the United States and Israel began bombing Iran, three sources told Reuters.

The weekend meeting is the first publicly reported since the start of the Iran war between the Palestinian militant group and the board, a new international body personally headed by Trump, which has been tasked with overseeing post-war Gaza.