The US President Donald Trump held a phone talk on Sunday over the response measures to the recent North Korean threats with his South Korean counterpart Moon Jae-in, Daily Star reported.
The sides exchanged views over the latest North Korean threat to cancel its summit.
The two leaders agreed to "work closely" for the success of the landmark summit in Singapore, Moon's press office said in a statement.
As reported earlier, North Korean summit is scheduled for June 12 in Singapore. Meanwhile, Pyongyang suspended negotiations with Seoul following US-South Korean joint military exercises, calling them a provocation.
Pyongyang said that North Korea will negotiate with the US if Donald Trump is interested not only in solving the nuclear problem, but also in improving relations with Pyongyang.
Yesterday, North Korea demanded Seoul repatriate a dozen waitresses who fled to the South Korea two years ago.