WASHINGTON, March 2 – President Bush raised the pressure on Syria today, saying the world was “speaking with one voice” in demanding that Damascus pull its troops from Lebanon.A State Department official, meanwhile, expressed skepticism about a new Syrian vow to withdraw. President Bashar al-Assad of Syria, seeking to defuse international pressure, pledged in an interview with Time magazine this week that his troops would leave “maybe in the next few months.” He qualified this, however, saying that the redeployment of 14,000 troops would require extensive and time-consuming preparations. Mr. Bush, speaking at a community college in Arnold, Md., applauded the message Secretary of State Condoleezza Rice had delivered a day earlier in London. She said that Damascus was “out of step” with the world’s desires for a free Lebanon. Her French counterpart, Michel Barnier, who appeared with her, agreed.