Obama asks China to help rein in North Korea

President Barack Obama urged China on Sunday to help rein in North Korea instead of "turning a blind eye" to its nuclear ambitions and warned Pyongyang of tighter sanctions, Reuters reported.

"North Korea will achieve nothing by threats or provocations," Obama said after a tour of the DMZ, the heavily fortified border between the two Koreas.

The BBC reported the warning is a reaction to North Korea's plans to launch a long-range missile in the next three weeks which it says will put a satellite in orbit.

More from GlobalPost: Obama tests his sway over North Korea

The US and South Korea say it would violate a UN ban on nuclear and missile activity and jeopardize an agreement Pyongyang reached last month to receive food aid in exchange for a partial freeze on nuclear activities and an end to ballistics tests.

Obama is in Seoul for three days to attend the 2012 Seoul Nuclear Security Summit. According to the Associated Press, both North Korea’s planned long-range missile launch and Iran’s pursuit of nuclear power are high on the agenda.

North Korea says the launch is scheduled in mid-April, to coincide with the 100th anniversary of the birth of the country late Great Leader Kim Il-sung.

Obama’s arrival also comes one the second anniversary of the sinking of the South Korean warship, Cheonan, in which dozens of sailors died when the ship was hit by what is believed to be a North Korean torpedo. Pyongyang has denied responsibility.

More from GlobalPost: Old problems plague new India

Sign up for our daily newsletter

Sign up for The Top of the World, delivered to your inbox every weekday morning.