NATO's chief accused Azerbaijan of undermining peace efforts with Armenia by pardoning a soldier who had murdered an Armenian officer and warned Friday, Sept 7 that there must be no return to war, according to Reuters.

NATO Secretary General Anders Fogh Rasmussen said he was "deeply concerned" about Azerbaijan's decision to clear Ramil Safarov and its impact on the Nagorno Karabakh conflict settlement.

"There must be no return to conflict between Armenia and Azerbaijan," Rasmussen told students during a visit to a diplomatic academy in Azerbaijan's capital Baku. "There is no military solution to the dispute,” he added.

"I am deeply concerned by the Azerbaijani decision to pardon Ramil Safarov. The act he committed in 2004 was a crime which should not be glorified, as this damages trust and does not contribute to the peace process," said Rasmussen, who was due to meet President Aliyev later in the day.

Azerbaijan sparked the indignation of world powers by pardoning Safarov after the army officer was repatriated last week from Hungary, where he had served eight years of a life term for murdering Armenian officer Gurgen Margaryan while the latter slept.

The 35-year-old criminal was treated as a hero upon his return, promoted to major and given an apartment and back pay for his years in jail.

Hungarian authorities say Azerbaijan had promised to uphold the sentence handed down to Safarov.