Kim Song -- Pyongyang's permanent representative at the UN -- said the incident was an 'unlawful and outrageous act'.
In February, North Korea's ambassador to the United Nations, Kim Song, issued an unusual appeal for urgent food assistance.
The Wise Honest was slowly towed to the port of Pago Pago during a cloudy Saturday morning and docked at the main docking section of the port that afternoon.
Kim has accused Washington of acting in "bad faith", and given it until the end of the year to change its approach.
The tests came five days after North Korea fired multiple short-range projectiles into the East Sea from Wonsan.
The ship was originally seized from the North Koreans by Indonesian maritime authorities in April 2018.
The launch came just days after North Korea carried out a military drill and fired multiple projectiles, with at least one believed to be a short-range missile.
The North Korean statements implied that Saturday's weapons launch counters joint military drills conducted by the US and S Korea.
South Korea's military initially said the North had fired "short-range missiles" but within an hour was describing them as "projectiles".
Trump said the two had also talked about trade, and his only public comment on the discussion was a tweet.
North Korea on Saturday carried out a test of rocket launchers and unspecified tactical guided weapons
There remains some uncertainty over what was tested.
Pyongyang had tested "240-mm and 300-mm multiple rocket launchers and a new type of tactical guided weapons with a range of around 70 to 240 kilometres."
If it's confirmed that the North fired banned ballistic missiles, it would be the first such launch since the North's November 2017 test of an intercontinental ballistic missile.
The World Food Programme has said that "unfavorable climatic conditions, limited supplies of agricultural inputs, such as fuel, fertilizer have had significant adverse impact on NK's food corporation.