Washington  - The United States said Wednesday it was disappointed that Iran did not extend visas to the US women's badminton team to compete in an upcoming tournament in Tehran.

US State Department deputy spokesman Robert Wood said the team of eight players, a coach, a manager and two officials from the US Badminton Federation was returning to the United States after being unable to obtain visas in Dubai.

The two countries have not had formal diplomatic relations for decades, but have tried to promote sports and cultural ties to ease tensions and harness dialogue between Americans and Iranians.

Wood said it was "not a good sign" that Iran had not granted visas to the team to participate in the tournament that begins on Friday.

"We are very interested in trying to improve relations between the American people and the Iranian people," Wood said. "And this is not a good step forward, in terms of trying to promote people-to-people exchanges."

Last year, the Iranian national basketball team trained in the United States ahead of the Beijing Olympics, and the US wrestling team participated in a tournament in Iran, where the sport is highly popular.

The Iranian Foreign Ministry said the lengthy process made it impossible for the government to grant visas in time for the Fajr International Badminton Tournament.

The US Badminton Federation said it was "very disappointed" that visas were not received after it had completed the application process more than two months ago and "in plenty of time to meet all deadlines."

"We were told our visas had been approved and were asked to secure them in Dubai," the federation said in a statement. "It's unfortunate that we will not be able to compete and sincerely hope we will be extended another invitation in the near future." dpa