The UK was plotting for the Iranian national football team to defect on the pitch at the World Cup in Qatar, the minister of sport and youth has told the Iranian parliament, without providing any evidence. The sports minister, Hamid Sajjadi, told MPs the country’s enemies had attempted “the height of sedition”. He said the “Old Fox”, by which he meant the UK, had planned for Iran’s players to walk off the pitch at specified moments and seek to defect. Sajjadi claimed the Iranian authorities had foiled the plot. He was willing to substantiate his claims in a private session, in what appears to have been part of a failed attempt to stave off an MPs’ vote of censure for the state of the national game, after the team was knocked out of the World Cup at the group stage. Many prominent Iranian footballers have been subjected to harassment by state security services for supporting the protests that have swept the country, but this was the first time a minister claimed there was a plot to subvert the Islamic Republic on the pitch at the tournament. His remarks came as an Iranian chess player, Sara Khadem, arrived in Spain on Tuesday after receiving what a source close to her said were warnings not to return to Iran after competing without a hijab at an international tournament in Kazakhstan. Khadem, born in 1997, took part in last week’s FIDE World Rapid and Blitz Chess Championships, in Almaty, Kazakhstan, without wearing a hijab, the mandatory headscarf under Iran’s dress codes. The source, who did not want to be named due to the sensitivity of the matter, said Khadem subsequently received multiple phone calls in which individuals warned her against returning home after the tournament, while others said she should go back, promising to “solve her problem”. The sports minister’s claims, for which there is no evidence, underline the atmosphere of paranoia that surrounded the men’s national team at the World Cup as many of the players struggled with conflicting pressures from protesters and officials. The claims did not stop him from being censured by the parliament, which accused of him of allowing foreign-based players and coaches to be given massive salaries. Over the past three months a number of Iranian footballers have been publicly threatened and harassed by the authorities. The former Iran national captain Ali Karimi was forced to flee the country after he expressed support for the protesters on social media, and all his properties and assets in Iran were confiscated by the order of the judiciary. The football manager Ali Daei has also been banned from leaving Iran.