A last-ditch plea is to be made to the European Court of Human Rights to block the extradition of a retired British businessman to the US.
The American authorities want to put Christopher Tappin on trial accused of conspiring to sell components for Iranian missiles.
The 64-year-old, from Orpington, Kent, denies unlawfully attempting to export batteries for Hawk air defence missiles and says he was the victim of entrapment in a "sting" organised by US government agents.
His long legal battle through the UK courts to block his removal ended in failure early today when High Court judges Lord Justice
Hooper and Mr Justice Cranston refused to allow him to take his case to the Supreme Court.
Refusing permission, Mr Justice Cranston said time would now begin to run for his removal to the US.
Later, Karen Todner, managing director of Kaim Todner Solicitors Ltd, acting for Tappin, said an application would be lodged with the European Court "in the next few days".
It will be an application for "Rule 39" relief staying Tappin's removal pending a further hearing of his case in Europe.
Ms Todner said Government solicitors had agreed not to extradite for 14 days to allow the application to be made.
His fight against extradition comes as Richard O'Dwyer, 23, battles his own case against US authorities.
Earlier this month the High Court judges rejected Tappin's challenge to a decision by district judge John Zani at City of Westminster Magistrates' Court last February that extradition could go ahead.
They said the entrapment argument was "unsustainable" and extradition would not be "oppressive" or a breach of human rights.
The judges also ruled the charges which the president of the all-Kent Golf Club Union faced were "extraditable offences", and they had to accept the extradition request was made "in good faith".
Tappin, a former director of Surrey-based Brooklands International Freight Services, said he had become trapped in a "nightmare" and believed he was exporting batteries for the car industry in the Netherlands.
Mr Justice Cranston said the allegation against Tappin, in broad outline, was that he had participated in the conspiracy with another UK citizen, Robert Gibson, who operated an export business in Cyprus, and American citizen Robert Caldwell. Others involved have not been named.
An investigation was launched by the US Department of Homeland Security, Immigration and Customs Enforcement (ICE), using a shell company, Mercury Global Enterprises (MGE), staffed by agents pretending to be members of the business.
In 2007 an ICE agent charged Tappin and the other alleged conspirators with criminal offences.
After his arrest, Gibson agreed - without Tappin knowing - to co-operate with the US authorities and told them he was buying the technology and the Hawk batteries for a long-time Iranian customer in Tehran.
Gibson pleaded guilty in a Texas court and was sentenced to a two-year jail sentence in February 2007.