"I am ready to serve the Iranian national soccer team because I have always loved my country," the 29-year-old Karimi told reporters after a Persepolis training session on Monday evening.
"If the Iranian side is to qualify for the 2010 World Cup, a professional program is required," the former Bayern Munich player added.
According to Persepolis' Portuguese manager Nelo Vingada, Karimi can solve the Iranian team's problems with his great experience.
"Karimi is a highly experienced player. He can help his country's outfit."
The 2004 Asian Player of the Year quit the national soccer team over a dispute with Iran's Football Federation (IFF) officials.
Iran is drawn in Group B of the 2010 World Cup qualifiers along with Saudi Arabia, South Korea, the UAE and North Korea. It will play its next match against Saudi Arabia at Tehran's Azadi Stadium on March 28th.
South Korea currently tops the group, with eight points, while North Korea places second with seven points. Iran is on the third spot with six points, two points clear of Saudi Arabia. The UAE is at the bottom with just one point.
The top two teams in each group will qualify for the 2010 World Cup finals. Third-place teams will compete in a two-leg play-off, with the winner taking on the Oceania zone victor, New Zealand, for a place in the World Cup.