Assuring New Delhi of his "steadfast support" in catching the perpetrators of Mumbai terror attacks, US President-elect Barack Obama has said that India has the sovereign right to go after terrorists to protect itself.

"Sovereign nations obviously have a right to protect themselves," said Obama, who takes over from President George W Bush on January 20, at a news conference in Chicago after rolling out his national security team.

The President-elect, who had during the election campaign said that if there was irrefutable evidence of al Qaida leaders and training camps in Pakistan he would go after them with or without Pakistan's permission, was asked if India has that same right.

"Beyond that, I don't want to comment on the specific situation that is taking place in South Asia right now," he said, adding, "I think it is important for us to let the investigators do their job in making a determination in terms of who was responsible for carrying out these heinous acts."

But "I can tell you, my administration will remain steadfast in support of India's efforts to catch the perpetrators of this terrible act and bring them to justice, and I will expect that the world community will feel the same way," he said.

Obama said his newly minted national security team had met Monday "to discuss the situation in Mumbai and some of the challenges that we face in the months and years ahead," and he was "confident that this is the team we need to make a new beginning for American national security."

Obama was a little more circumspect when first asked if India would be justified in going after the terrorists responsible for the Mumbai attack, which New Delhi has said were linked to bases in Pakistan.

"First of all, I think it's important to reiterate that our condolences, our thoughts and prayers go out to the people of India, the families that have been affected and obviously we are heartbroken at the deaths of the six Americans that were caught up in this tragedy," he said.

Obama said, "I have spoken to Prime Minister Manmohan Singh and expressed these concerns to him; an investigation is taking place."

"I was briefed by Secretary (Condoleezza) Rice throughout the weekend, (and) she's on her way to the region. We've sent FBI to help on the investigation and this is one of those times, where I have to reiterate - there's one president at a time."

Obama said: "We are going to be engaged in some very delicate diplomacy in the next several days and weeks, (and) so I think it would be inappropriate for me to comment."

"But, what I can say unequivocally is that both myself and the team that stands besides me, are absolutely committed to eliminating the threat of terrorism and that is true wherever it is found," he said.

"We cannot tolerate a world where innocents are killed by extremists based on twisted ideologies," said Obama.

"We're going to have to bring the full force of our power -- not only military but also diplomatic, economic and political -- to deal with those threats. Not only to keep America safe but also to ensure that peace and prosperity continue around the world."

"The situation in South Asia as a whole and the safe havens for terrorists that have been established there, represent the single most important threat against the American people," he said.

Noting the situation in Afghanistan has been worsening, he said: "We're going to have to mobilise our resources and focus our attention on defeating al Qaeda, (Osama) bin Laden, and any other extremists groups that intend to target American citizens."