The Iran men's national team wore black armbands and held schoolbags as their national anthem played before a match with Nigeria as a protest against the deadly strike on a primary school on the first day of the Iran war.

The attack on Shajareh Tayyebeh school last month killed at least 168 people, including about 110 children, Iranian officials have said.

US media have reported that American military investigators believe their own forces were likely responsible for hitting the school in Minab in southern Iran unintentionally.

The UN's human rights chief has urged the US to conclude its investigation and publish its findings into the attack.

Before kick-off in their friendly fixture against Nigeria in the Turkish resort town of Belek, the Iran players, including former FC Porto and Inter Milan striker Mehdi Taremi, were seen holding pink and purple bags with ribbons on them.

"The players are holding the school bags close to their heart in remembrance of the 165 girls the Americans killed in an Iranian school," a media officer for the team told Reuters.

Iranian officials have blamed the US and Israel for the attack on the school, which was adjacent to an Iranian Revolutionary Guard Corps (IRGC) compound, but neither country has accepted responsibility.

Iran are among the countries who have qualified for this summer's World Cup but their participation in the tournament, to be hosted by the US, Mexico and Canada from 11 June, remains in doubt.

They are scheduled to open their World Cup campaign against New Zealand and Belgium in Los Angeles before their final group game against Egypt in Seattle.

However, US President Donald Trump said earlier this month it would not be "appropriate" for them to take part "for their own life and safety".

Mehdi Taj, the head of Iran's football federation, then said the country will not travel to the US for what would be a fourth consecutive World Cup appearance.

"When Trump has explicitly stated that he cannot ensure the security of the Iranian national team, we will certainly not travel to America," Taj said in a post, external on a social media account belonging to the Iranian embassy in Mexico.

Taj said Iran were negotiating with Fifa to hold their matches in Mexico but the governing body appear to have ruled out that possiblity.

Iran, who were beaten 2-1 by Nigeria on Friday, will face Costa Rica in another friendly in Turkey on Tuesday.

Earlier this month, the country's women's national team players declined to sing the national anthem during an AFC Women's Asian Cup match, leading to a host on Iranian state TV calling them "traitors".

A number of the players had initially sought humanitarian visas to stay in Australia after concerns they would face repercussions for their protest but all members of the team eventually returned to Iran after dropping their bids for asylum. (BBC)

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