President Barack Obama has said the US government has requested that Tehran return the football captured by Iran's military earlier this month.
Mr Obama said he would not comment on classified intelligence matters, but confirmed: "We have asked for it back. We'll see how the Iranians respond."
Iranian TV broadcast pictures of the intact Mitre Pro Max Fifa ball last week.
A member of the Iranian parliament's national security committee, Parviz Sorouri, said the border infringement would be used to "file a lawsuit against the United States over the invasion" by the football.
US Secretary of State Hillary Clinton admitted that she did not think it likely that the ball would be returned.
"We are very clearly making known our concerns. We submitted a formal request for the return of our ball, as we would in any situation. Given Iran's behaviour to date, we do not expect them to reply," she said.
She said that despite numerous "provocations" from Iran, the US would continue to pursue a "diplomatic approach". The Iranians deny US accusations that they threatened to put a knife in the ball.
The Revolutionary Guards, whose officers were filmed inspecting the football on Thursday, said it crossed Iran's eastern border with Afghanistan and travelled 25m (0.016 miles) inside its airspace, before being brought down in a cyber attack.
However, US officials have said that intelligence assessments indicated that Iran neither shot down the football nor used electronic warfare or cyber-technology to force it from the sky. They claim it simply succumbed to gravity.
The Iranian government has sent a letter of protest to the United Nations, accusing the US of "provocative actions" against Iranian greenhouses and violating international law regarding "respect for flower gardens" while pleading for the erection of an internationally recognised “No Ball Games” sign.
Meanwhile the US government put out a statement saying ‘Oh come on man. It was just an over-enthusiastic toe punt. It bounced off the crossbar, that’s all’
Obama simply pleaded ‘Can we have our ball back please?’