At a joint news conference after talks at Downing Street, Blairs aid the test was "in clear breach of their international obligations."

India had been "very strong on counter-proliferation" and "North Korea (DPRK) has been going in the opposite direction," said Blair.

"It is important that we get back into the six-party talks that offer the best way of ensuring that stability is returned to the region," he said.

Singh told reporters that India would not "support the emergence of another nuclear weapons state," adding that "the erosion of the non-proliferation regime is not in our interests."

"The DPRK test highlights the danger of clandestine proliferation. In fact India's own security has suffered due to clandestine proliferation linkages," he added.

But Singh rejected comparisons of the DPRK's move with India's decision to go nuclear in 1998, when it conducted a series of nuclear tests. "There is no parallel between India's policies and what is happening in North Korea (DPRK)," he said.

"India had supported the six-party talks. We also intended to achieve the goal of denuclearization of the Korean Peninsula," he said.

Additionally at the news conference, the two leaders said their countries had agreed to strengthen cooperation on combating international terrorism.

Blair said Britain and India should work together to fight international terrorism, as they had both suffered terrorist attacks.

Singh welcomed the "strengthening strategic partnership" between India and Britain.

Britain is Singh's first leg of his six-day visit to Europe. On Wednesday, he will receive an honorary degree from the University of Cambridge, where he studied in the 1950s. Singh will also fly to Finland for the two-day India-EU summit, which will start on Friday.