He held discussions with ARD chairman Amin Fahim, Nisar Ali Khan, Zafarul Haq and Siddiqul Farooq.
McKinnon declined to speak further specifically on the issue, saying that he would be sending a detailed report to the Commonwealth Ministerial Committee pertaining to his meetings with Pakistani leaders.
He said that the Commonwealth wanted full restoration of democracy in Pakistan, and added: "We will always support this cause."
ARD leaders apprised McKinnon of the political situation, the passage of the 17th Amendment and the recent passage of the 'dual-office bill'. The alliance leadership dubbed the legislation as black law and asserted that there was no constitutional provision for an individual to hold two offices simultaneously.
They drew his attention towards President Musharraf's commitment under an agreement with the Muttahida Majlis-i-Amal and his promise to the nation to doff his uniform before or on December 31.
They expressed strong reservations over the state of the Parliament and the way the Constitution and the state institutions were being run.
Talking to newsmen, Amin said that the worst kind of dictatorship had been imposed on Pakistan under General Pervez Musharraf.
"We discussed all matters pertaining to democracy and the Parliament with the secretary-general and apprised him of the flagrant violations of the Constitution by the rulers," he said.
However, he said, the main focus of talks was that no one could remain army chief and the president at the same time.
Amin said he told McKinnon that ARD was planning to launch a countrywide movement against the rulers for their dictatorial policies. "We made it clear to him that the recent dual-office bill has made the Parliament irrelevant and meaningless."
Earlier, McKinnon said that the Commonwealth fully backed recent initiatives by Islamabad and New Delhi, adding that Pak-India talks were a healthy sign. "The Commonwealth wants cordial relationship between the two countries," he remarked.