ISLAMABAD - US Ambassador to Pakistan Cameron Munter Wednesday called on the Chief of Army Staff General Ashfaq Parvez Kiyani and exchanged views on the strained US-Pakistan relations, sources said. The ISPR said that it had no knowledge of the meeting. However, diplomatic sources told The Nation that the US envoy who met with General Kiyani on his request discussed the challenges both the countries are facing in improving the bilateral relations. According the sources, the Army Chief ostensibly rejected the ambassadors demand for military action against militants in North Waziristan on the plea that any military action has to be decided by the government. General Kiyani, the sources said, also took serious exception of the CIA operated drone strikes in Waziristan as it was counter productive and was promoting anti-US sentiments among the tribesmen. Confirming the meeting the US Embassy spokesman said it was a private meeting and The embassy normally does not share private meetings details with media, adding that the Ambassador normally meets different members of the society while being strategic partner with Pakistan. Monitoring desk adds: A private TV channel reported that Cameron lodged a complaint regarding Islamabads move of putting curbs on inter-city movement of US diplomats,. Meanwhile, four officials of US Embassy in Islamabad were sent back to Islamabad when they tried to enter Peshawar City without holding NOC and incomplete documents. On Wednesday morning, four US diplomats including Denis Wynne, Wilmer Case and Joseph Edward, attempted to enter Peshawar by two vehicles bearing numbers PB-491 and SV-406, however, police officials at Peshawar Motorway Toll Plaza stopped them and asked for their NOC. Upon the inquiry of police officials, all the four US diplomats were sent back to Islamabad, as they did not hold the required documents for entering into Peshawar.