President Obama will address the nation on how he will combat the threat posed by the Islamic State in Iraq and Syria Wednesday evening at 9 p.m. ET, the White House said Tuesday.

Obama will make speak from the State Floor of the White House. The White House said he will outline how the United States will "degrade and destroy" the Islamic State and go on the offensive against the group, which decapitated two American journalists last month. The president ordered air strikes against the group in Iraq last month, but has not yet outlined how he plans to counter the group in Syria.

Obama will meet Tuesday afternoon with members of Congress about the Islamic State. Congressional aides said Obama is unlikely to seek formal authorization for a military strike against the Islamic State in Syria.

(AP Photo/Charles Dharapak, File)

The president has said Wednesday's remarks will not include an announcement that the United States is sending ground troops to Syria or Iraq. In an interview with "Meet the Press" Sunday, Obama likened whatever offensive has or will take place to counterterrorism attacks that have taken place since the attacks of Sept. 11, 2001.

"I just want the American people to understand the nature of the threat and how we're going to deal with it and to have confidence that we'll be able to deal with it," Obama said of the threat on "Meet the Press."

According to a Washington Post/ABC News poll, Americans widely support air strikes against the Islamic State in Iraq and Syria -- a marked shift from last year, when a majority didn't support Obama's case for military action in Syria.