North Korea used its embassy in Berlin to obtain technology secretly for its nuclear weapons programme, according to new disclosures from Germany’s domestic intelligence service.

Repeated moves by the embassy to buy equipment that could be used for ballistic missiles and nuclear weapons were uncovered over the past two years.

“We discovered procurement activities taking place there, which we believe were focused on the missile program, and also to some extent on the nuclear program,” said Hans-Georg Maassen, the head of the Bundesamt für Verfassungsschutz (BfV), or Office for the Protection of the Constitution.

“When we detect something of this sort, we take steps to prevent it,” Mr Maassen told German television. “But we can't guarantee that we are able to detect and prevent every case.”

The disclosures were made by Mr Maassen in an interview with NDR television for a report that is to be aired in full on Monday.

In brief extracts released in advance, the intelligence chief described how the North Korean embassy had purchased “dual use” technology that could be employed for civilian or military purposes.

“They were acquired in other markets or front companies were used to buy them in Germany,” he said.