Mr. Bush said, "The bombings should remind all of us that there is an enemy in this world that is willing to kill innocent people, willing to bomb a wedding celebration in order to advance their cause."
He says those who love freedom and respect every human life must stand together to take on the terrorists.
Mr. Bush said, "We have an obligation and a duty to remain strong and remain firm and to bring these people to justice."
The comments came as Mr. Bush sat down for a meeting at the White House with the president of Yemen, Ali Abdullah Saleh. Speaking through an interpreter, the Yemeni leader promised to work with the United States in combating terror, saying they have made a joint declaration of war against terrorism and extremism.
Mr. Saleh said, "I am here to reaffirm Yemen's position is clear and firm. Our resolve is firm to continue to work with the United States and the international community in combating terror."
Earlier in the day, President Bush spoke by telephone with Jordan's King Abdullah. Mr. Bush said he expressed America's concern and compassion for the victims and their families.
White House press secretary Scott McClellan told reporters that during the call, both agreed that it is important to remind the world that the terrorists cannot shake their will.
Mr. McClellan said it is unclear at the moment exactly who is responsible for the triple bombings that have claimed 56 lives. But he said the attacks had all the hallmarks of the al-Qaida terrorist network.
