U.S. President Barack Obama is to address in his Nobel Peace prize acceptance speech in Norwegian capital Oslo the recent decision to send 30,000 more U.S. troops to Afghanistan, the White House said on Wednesday.

"The president will address the notion that last week he authorized a 30,000-person increase in our commitment to Afghanistan, and this week accepts a prize for peace," said White House spokesman Robert Gibbs, in a daily press briefing before Obama's departure on Wednesday night.

Responding to a question about whether Obama feels embarrassed, Gibbs said Obama is proud of the steps his administration has taken to re-engage the world.

"That re-engagement is to bring increased peace and stability to this big planet," Gibbs said, noting the Nobel committee has recognized that re-engagement.

Obama is to accept the prize Thursday in Oslo. The irony of his being both Nobel laureate and war time president has raised many eyebrows.

Gibbs said Obama "understands" he isn't "in the same discussion as Mandela and Mother Theresa." Nelson Mandela, former South African president, and Mother Theresa were both Nobel Peace Prize recipients.