The U.N. Security Council unanimously passed tougher sanctions against North Korea Thursday targeting the secretive nation's nuclear program hours after Pyongyang threatened a possible "preemptive nuclear attack." "These sanctions will bite, and bite hard," U.S. Ambassador to the United Nations Susan Rice said after the vote. China, North Korea's key ally, could have used its veto power to block the sanctions. Instead, after weeks of negotiating, it signed on to the final draft. "China is a country of principle," China's U.N. Ambassador Li Baodong said. "We are firmly committed to safeguarding peace and stability on the Korean peninsula." Leading up to the vote, Pyongyang ratcheted up its bellicose rhetoric.
@highlight
U.S. Ambassador Rice: The sanctions will "bite hard"
@highlight
China is "firmly committed" to peace on the Korean peninsula, ambassador to U.N. says
@highlight
The resolution will clamp down on North Korea's officials, banks and cargo
@highlight
Analysts say China is a key to determining whether the sanctions deter North Korea
North Korea casts U.N. sanctions as part of an aggressive, @placeholder-led conspiracy against it.