Since then Kim has said the North would not test nuclear devices or ICBMs but diplomacy has stalled in recent weeks.
When asked about the missiles, Trump said, "Nobody is happy about it, but we're taking a good look and we'll see" Reuters reported.
North Korea has effectively pulled back from engagement with Washington since the Hanoi meeting between its leader Kim Jong Un and Trump collapsed without agreement on USA demands for the dismantling of Pyongyang's nuclear program and Kim's demands for relief from punishing sanctions.
The North had not launched any missiles since November 2017, shortly before once reclusive Kim embarked on diplomatic overtures. "But I don't think they're ready to negotiate", Trump told reporters. Developed in the 1970s, the Iskander is a road-based mobile launch system that can fire multiple ballistic and cruise missiles.
South Korean President Moon Jae-in warned Kim his actions risk "throwing cold water" on negotiations.
"I want to tell North Korea once again that it's not ideal to repeat actions that create various interpretations of its intent, raise concern and risk throwing cold water on the atmosphere of dialogue and negotiations", said Moon, a liberal who facilitated contacts between the United States and North Korea previous year.
A South Korean official, who spoke on condition of anonymity, said the projectile was believed to have flown around 420km.
Kim Jong Un's father Kim Jong Il was also a basketball fan and requested that the US invite Michael Jordan to North Korea during talks in 2000, but Jordan declined.
US President Donald Trump delivers a televised address to the nation on funding for a border wall from the Oval Office of the White House in Washington DC on 8 January 2019.
Sanctions against the North over its nuclear and missiles programmes remain in place.
Pyongyang fired two short-range missiles Thursday following an earlier drill the previous Saturday - the first in 18 months. Details from the meeting weren't immediately announced.
"They were smaller missiles, they were short-range missiles", he said.
North Korean dictator Kim Jong Un reportedly requested the US send "famous basketball players" to the Hermit Kingdom in an effort to normalize the relationship between the two countries.
In addition, North Korea's latest launches, apparently, are aimed at negotiating a suspension of the joint US-South Korean military exercises, which Pyongyang considers a threat, during the inter-Korean and US-North Korean dialogue. Those included increasing pressure for sanctions relief, and protesting Seoul's military buildup including the purchase of new F-35 fighter aircraft as well as joint military drills by the United States and South Korea, which North Korea complained about in statements defending the tests.
Cha added that by firing weapons that threaten South Korea but not the U.S., North Korea could be testing the Americans without causing the collapse of the nuclear talks.
The missile uses solid fuel, which allows the weapon to be easily moved and fired more quickly than those using liquid fuel, analysts said.
The expert noted that unless the situation changes, short-range missile tests are likely to continue.