A group of Iranians are said to have witnessed North Korea’s missile tests, deepening concern over Tehran's nuclear ambitions.

U.S. Assistant Secretary of State Chris Hill made the claim at a Senate hearing, believed to be the first public suggestion that Iranian officials saw the seven tests. There are worries in Washington about links between Iran and North Korea, and American accusations that both states have secret nuclear weapons programmes. Tehran refuses to be drawn on the package of incentives offered by the international community and to halt nuclear enrichment.