leader of North Korea Kim Jong Un could soon be preparing to launch a new submarine capable of launching ballistic missiles, according to a US-based think tank.

What happened: According to a report in Reuters, 38 north, which monitors North Korea, said six barges and ships have gathered near the quay of the construction hall on the east coast of the country. They were discovered from September 18th. 38 North mentioned in the report that its observation was based on commercial satellite imagery from Sinpo South Shipyard.

.See also: US seeks diplomacy with North Korea while Kim Jong-Un enacts law on use of nuclear weapons, including pre-emptive strikes

“While barges and a dry dock were occasionally observed around the submarine launch quay in the main construction hall, the presence of six ships and barges in this area had not been previously observed,” the report reads.

It concluded that the activity suggests Kim may be preparing to launch a submarine.

Why it matters: The report comes hours after the US President Joe Bidenin a speech to the UN General Assembly on Wednesday, blasted North Korea for “blatant violation of UN sanctions”.

Meanwhile, earlier this month, the US sought diplomacy with North Korea after the supreme leader introduced a new law formalizing the right to use pre-emptive nuclear strikes to protect the country. That White House press secretary Karine Jean Pierre said the US had no hostile intentions towards the country and continued to seek diplomacy with Kim.

See also: Biden calls Putin on UN appearance for ‘lying’ and ‘open nuclear threat’