The Americans say they will consider taking the matter to the Court of Arbitration for Sport in Lausanne, Switzerland, after they were stripped of first place for an illegal changeover.

US team director Dennis Pursley was adamant that his team should be reinstated.

"The video back-up shows that the changeover was legal," he said.

"The Jury of Appeal did not look at the video but took their decision based on a statement from a Seiko timing official and said there was nothing wrong with the timing system.

"Even if they believed that was the case, then there have been enough incidents since to show that the timing system has been erroneous. That warrants a reconsideration of the 4x200m result."

Pursley is one of 16 coaches who has signed a letter to Fina saying they were "gravely concerned" about the timing system.

The system has so far failed 16 times in the championships.

If the Americans are successful in their appeal, Britain will lose their first gold medal in 26 years.