Despite claims by the United States that there is "irrefutable evidence" Iran is smuggling weapons to the Taliban in Afghanistan, the defense minister of Afghanistan today disputed those claims. "There has been evidence of weapons, but it is difficult to link it to Iran," said Abdurrahim Wardak in an interview with the Associated Press in Brussels today. "It is possible that [they] might be from al Qaeda, from the drug mafia or from other sources." Wardak joined a meeting of NATO defense ministers in which it was decided today more trainers would be deployed to Afghanistan to work with the army there. Earlier this week, U.S. Undersecretary of State Nicholas Burns told CNN there was "irrefutable evidence" that the smuggled weapons shipments were coming from Iran’s government. Last week, ABC News was first to report on a coalition analysis that concluded there is clear evidence of Iran’s involvement. "This is part of a considered policy," said the analysis, "rather than the result of low-level corruption and weapons smuggling." Do you have a tip for Brian Ross and the Investigative Team? The coalition analysis said munitions recovered in two Iranian convoys, on April 11 and May 3, had "clear indications that they originated in Iran. Some were identical to Iranian supplied goods previously discovered in Iraq." The April convoy was tracked from Iran into Helmand province and led to a fierce firefight that destroyed one vehicle, according to the official analysis. A second vehicle was reportedly found to contain small arms ammunition, mortar rounds and more than 650 pounds of C4 demolition charges. A second convoy of two vehicles was spotted on May 3 and led to the capture of five occupants and the seizure of RPG-7mm rockets and more than 1,000 pounds of C4, the analysis said. Also among the munitions are components for the lethal EFPs, or explosive formed projectiles, the roadside bombs that U.S. officials say Iran has provided to Iraqi insurgents with deadly results. Click Here for Full Blotter Coverage.