"Mr Gaddafi has lost legitimacy and he needs to leave," Obama said in a joint media availability with visiting Danish Prime Minister Lars Lokke Rasmussen at the White House.
Obama said he and Rasmussen agree that international community have to speak firmly against any violence that`s directed at civilians.
"We have to make sure to provide humanitarian assistance, both inside of Libya as well as along the border regions where so many people have left; and that it`s going to be very important for us to look at a wide range of options that continue to tighten the noose around Mr Gaddafi and apply additional pressure," he said.
"So we will be continuing to coordinate closely both through NATO as well as the UN and other international fora to look at every single option that`s available to us in bringing about a better outcome for the Libyan people," Obama said.
Condemning the violent repression of the Libyan people, Rasmussen said European leaders gathered last Friday, sent a very strong signal to Gaddafi.
"He should be history. He has lost his legitimacy, as you (Obama) just mentioned. I think it`s important that the international society examine all options to protect the Libyan people," he said.
"Fortunately, change is going on in other countries in the Middle East and North Africa as well, and we had an opportunity to discuss it`s basically a very positive transition in Egypt and Tunisia," the Prime Minister said.
During his stay here Rasmussen met with House Minority Whip Steny Hoyer and US House of Representatives Speaker John Boehner.
During the meeting, Hoyer referred to Denmark as one "of the very closest allies of the United States" and thanked the Danish administration for its commitment to "making the world a better and safer place".