US Secretary of State John Kerry warned North Korea Monday of possible fresh sanctions as he slammed Kim Jong-Un\’s \"egregious\" leadership with its reliance on reckless provocation and \"grotesque\" executions.\r\n

US Secretary of State John Kerry warned North Korea Monday of possible fresh sanctions as he slammed Kim Jong-Un's "egregious" leadership with its reliance on reckless provocation and "grotesque" executions.

Speaking in the South Korean capital Seoul, Kerry said the recent test of a new submarine-launched ballistic missile (SLBM) showed that North Korea had no genuine interest in engaging with the international community.

"Instead, it continues to pursue nuclear weapons and ballistic missiles, it continues to break promises and make threats, and it continues to show flagrant disregard for international laws," he told a joint press conference with South Korean Foreign Minister Yun Byong-Se.

"That is why it is important for us to ramp up international pressure for North Korea to change its behavior," he added, citing the possible use of further "sanctions or other means" to force Pyongyang to change course.

The impoverished but nuclear-armed state is already heavily sanctioned following a series of nuclear and missile tests staged in violation of UN resolutions.

Just over a week ago, the North said it had successfully test-fired the SLBM missile, defying a UN ban on its use or testing of ballistic missile technology.

A fully-developed SLBM capability would take the North Korean nuclear threat to a new level, allowing deployment far beyond the Korean peninsula and the potential to retaliate in the event of a nuclear attack.

Later on Monday Kerry was scheduled to give a comprehensive foreign policy speech on the use of cyber-space, including issues of cyber-security.