By
It said Obama will deliver the speech at the National Defense University at 7:30 pm (2330 GMT), a time when most Americans are home, many of them tuned to their televisions.
Obama will "update the American people on the situation in Libya, including the actions we've taken with allies and partners to protect the Libyan people from the brutality of Moamer Kadhafi, the transition to NATO command and control, and our policy going forward," the White House said.
Critics have complained that Obama has failed to clearly explain US goals and strategy in the seven-day-old, UN-mandated air campaign against the Kadhafi regime.