WASHINGTON -- U.S. Ambassador Susan Rice said Tuesday that North Korea is "trying to test whether they can intimidate the international community" with an its underground nuclear test and launching of short-range missiles.
"But we are united, North Korea is isolated and pressure on North Korea will increase," said Rice, who represents U.S. interests at the United Nations.
Her remarks came a day after President Barack Obama assailed Pyongyang, accusing it of engaging in "reckless" actions that have endangered Northeast Asia and the Korean peninsula.
Speaking a day after the U.N. Security Council condemned the tests as a "clear violation" of a 2006 resolution banning the regime from developing a nuclear program, Rice said she believes that Pyongyang "is surprisingly in tune to international reaction" and said she hoped that it can result in North Korea backing off from its nuclear intentions.
U.S. officials have been reluctant in this latest episode to discuss specifically what options are available for reining in Pyongyang, although neither the Obama administration nor the Bush and Clinton administrations before it ever publicly took the military response option off the table.
The goal is twofold, U.S. officials have suggested: To allow Pyongyang to neither have its own nuclear weapons program nor export nuclear materials to other nations or rogue states.
Across the spectrum of the American military and political establishment, there was harsh criticism of Pyongyang.
Secretary of State Hillary Rodham Clinton had telephone consultations with her counterparts in a number of countries and the chairman of the Joint Chiefs of Staff, Adm. Mike Mullen, said North Korea was further isolating itself.
Said Kerry: "It's so contrary to common sense and to the interests of the country."
Rice acknowledged that U.N. Resolution 1718, passed by the Security Council in 2006, lacked strong sanction enforcement provisions and said that more recently, "we actually put teeth" in a developing resolution to replace that one.
Asked why Pyongyang could be expected to honor any such resolution given its indifference in the past, she said that "North Korea is surprisingly in tune to international reaction, and they are trying to test whether they can intimidate the international community."
Rice also suggested that China is growing increasingly irritated with Pyongyang and said that likely presents the United States with a stronger diplomatic option, and more international consensus, this time around.
"China has interest in North Korea," she said. "They want to see North Korea stable and without nuclear weapons. China has played a constructive role. We and our partners need to agree on a package (of sanctions) that will cause North Korea to change its course."
"We leave the door open to diplomacy," she said. "We're prepared to step up our efforts to intercept and interdict prohibited cargo from North Korea, but obviously, we don't rule out any options."
Rice also credited Russia with helping increase international pressure on Pyongyang.
The ambassador was interviewed on CNN, ABC's "Good Morning America," CBS's "The Early Show," NBC's "Today" show and MSNBC.