WASHINGTON: Defense Secretary Robert Gates says the United States' relationship with Afghanistan is going to begin changing in July 2011.

Defense Secretary Robert Gates, right, and Secretary of State Hillary Rodham Clinton, confer at the conclusion of their testimony on Capitol Hill in Washington, Thursday, Dec. 3, 2009, before the Senate Foreign Relations Committee hearing on Afghanistan. [Agencies]?

When President Barack Obama announced this past week that he was sending 30,000 more troops to Afghanistan, he also set a timeline for starting troop withdrawals in July 2011.

Gates said the US will begin transferring responsibility for security district by district, province by province to the Afghans. And he said that Afghans should understand the nature of their relationship with the US will begin changing then as well. He said the economic, development and political aspects of the relationship will become a bigger part.