Washington, Nov 13 (IANS): North Korea continues to secretly develop its nuclear weapons programme despite months of talks with the US, according to a report released by a Washington-based think tank.

The Centre for Strategic and International Strategic Studies (CSIS) report released on Monday argues that, despite talks between US President Donald Trump and North Korean leader Kim Jong-un, Pyongyang is reinforcing thirteen secret facilities that serve primarily to store nuclear weapons, reports Efe news.

These improvements include the expansion of some of these bases and the construction of access roads.

The report includes satellite photos that show that in recent months North Korea has carried out a number of improvements to a series of facilities that would "support a missile launch in an emergency".

This information is a setback for President Trump, who in recent months has boasted about the progress made after his summit with Kim in Singapore on June 12, which led, among other gestures, to the decommissioning of the Sohae missile base, in the northwest of the country in July.

"North Korea's decommissioning of the Sohae satellite launch facility, while gaining much media attention, obscures the military threat to US forces and South Korea from this and other undeclared ballistic missile bases," CSIS said.

Kim agreed to abandon his nuclear program and was willing to be inspected by international organisations in exchange for the US to also make concessions.

However, in recent weeks, negotiations have cooled down as Pyongyang considers that it has already taken several steps but has not had the expected response from Washington, which has neither relaxed the sanctions nor cancelled its joint military manoeuvers with South Korea, something North Korea considers a provocation.