In a unanimous vote, the 15-nation council agreed to the resolution, drafted by the United States and France, which follows the release of a damaging U.N. report implicating top Syrian and Lebanese security officials in Hariri's Feb. 14 assassination.
"Syria has offered no truthful explanations to these serious allegations," Secretary of State Condoleezza Rice told the council, according to Reuters. "Instead it has chosen until now to dismiss the commission report as politically motivated."
China and Russia, which oppose economic sanctions against the Islamic nation before the U.N. inquiry is complete, forced the United States and France to remove stronger language making reference to such sanctions.
But the warning of possible punitive measures, which may later include economic sanctions, was passed under Chapter VII of the U.N. charter, a chapter that can be enforced through military action.
The two Western countries also agreed to remove a request that Syria renounce its support "for all forms of terrorist action and all assistance to terrorist groups," the Associated Press reported. The United States has accused Syria of allowing insurgents fighting U.S. forces in Iraq to freely cross its borders.
Monday's resolution requires that Syria detain any suspects in Hariri's murder and that U.N. investigators be allowed to decide where and when suspects are questioned. The resolution also requires the government to freeze the assets of and impose travel bans on suspects named in the final report, expected in December from U.N. investigator Detlev Mehlis.
"The people of the Lebanon have become all too acquainted with grief," British Foreign Secretary Jack Straw said Monday, the AP reported. "We owe them a better future, and this resolution is one way of providing them with that better future."
Syrian officials have denied a role in Hariri's death. Syrian President Bashar Assad has refused a request from Mehlis to be interviewed as part of the official inquiry.
Among the top suspects in the investigation are Assad's close advisors, his brother Maher Assad and his brother-in-law Assef Shawkat, who heads the country's military intelligence.
In an effort to rally support in the wake of the political crisis, Syrian officials have asked members of the Arab League to gather for an emergency meeting, the AP quoted Arab diplomats as saying. The meeting could be held as early as this week once Ramadan, the Muslim month of fasting and prayer, ends.
On Saturday, Assad reportedly gathered a judicial committee of his own to conduct an investigation into Hariri's death, according to the AP. In a presidential decree, he said the committee would cooperate with the U.N. investigation.