Washington (CNN) - Defense Secretary Robert Gates signed an order Friday to deploy the first wave of troops to Afghanistan as part of President Barack Obama's new strategy, a defense official confirmed to CNN.
The troops from the Army and Marines will be the first of 30,000 that are to be sent to Afghanistan by summer under the plan announced by Obama this week.
An official announcement is not likely before Monday, the officials said.
Approximately 1,000 Marines are expected to deploy this month, military officials told CNN previously. The Army may not deploy the first soldiers until at least March, Army officials said Friday.
Testifying before a congressional committee, Adm. Michael Mullen, chairman of the Joint Chiefs of Staff, said this week that a "significant" number of troops will arrive in the spring and summer, with the final troops moving to Afghanistan by late summer or early fall.
Meanwhile, the White House said Obama would meet with Gen. Stanley McChrystal, the U.S. commander in Afghanistan, and Karl Eikenberry, the U.S. ambassador in Kabul, on Monday. Both are expected to testify before Congress next week.
- CNN's Mike Mount contributed to this report