North Korea is likely to carry out more missile tests if they "don't feel satisfied" with US talks.
That's according to US Defence Secretary Mark Esper, who added that it was important to "get serious".
"I've been watching the Korean Peninsula for maybe a quarter of a century now. So I'm familiar with their tactics, with their bluster and I think we need to get serious and sit down and have discussions about a political agreement that denuclearizes the Peninsula," he said.
Denuclearisation talks between both countries have reached a deadlock, with Pyongyang continuing to conduct a series of weapons tests over unrelenting sanctions from the US.
There are threats that North Korea could restart intercontinental ballistic missile (ICBM) testing, as US special envoy for North Korea, Stephen Biegun, urged Pyongyang to restart talks.
"I would like to remain an optimist that we can keep moving forward with regard to negotiations because the alternate is not a positive (one)," Esper added.
A state of relative calm prevailed around the Strait of Hormuz on Saturday, after days of sporadic flare-ups, as the United States waited for Iran's response to its latest proposals to end more than two months of fighting and begin peace talks.
A car bombing at a police post killed at least three officers in northwestern Pakistan on Saturday and was followed by an ambush on police personnel rushing to the scene to provide backup, security officials said.
An Israeli strike on the southern Lebanese town of Saksakiyeh killed at least seven people, including a child, and wounded 15 on Saturday, Lebanon's health ministry said.
The cruise ship hit by a deadly hantavirus outbreak arrived early on Sunday near the Port of Granadilla in Tenerife, Reuters footage showed, where it will anchor for the evacuation of the passengers and some of the crew.