Americans must stay "strong and resilient" in fighting terrorism, the Obama administration's top homeland security adviser said in Washington on Wednesday.

The United States must focus on al-Qaida and other terrorists as murderers, not religious leaders, John Brennan, assistant to the president for homeland security and counter-terrorism, said, speaking at the Center for Strategic and International Studies, a bipartisan foreign policy think tank in Washington.

According to the reports, he added the response must be to deprive terrorists of their safe havens with scalpel-like precision to avoid killing civilians. He also said the United States must marshal its resources so as not to become overextended and continue to develop a legal framework that includes both civilian and military prosecutorial options.

It was also reported that Brennan made his comments the day before President Barack Obama is to release his national security strategy, which he said will reflect the "president's vision for confronting the most daunting challenges of our time while seizing the opportunities of an increasingly globalized world."

He further said that the United States, "will disrupt, dismantle and ensure a lasting defeat of al-Qaida and violent extremist affiliates."

He said, "We will deny al-Qaida and its' affiliates safe haven. We will secure the world's most dangerous weapons, especially the nuclear materials that al-Qaida seeks and would surely use against us. We will build positive partnerships with Muslim communities around the world. And most importantly, we will protect our homeland."

He called it "a multi-departmental, multinational, and indeed, a multigenerational, effort."

Brennan also said "As a strong and resilient nation, the United States will not cower in the face of a small band of cowards who hide in the shadows and send others to their slaughter and to slaughter the innocents." (With Inputs from Agencies)