(Adds background) By Jeremy Lovell LONDON, Nov 6 (Reuters) - The Commonwealth on Tuesday called a special ministerial meeting for next week in London to discuss the state of emergency in Pakistan. Commonwealth Secretary-General Don McKinnon called the extraordinary meeting of the Commonwealth Ministerial Action Group (CMAG). Foreign ministers from Canada, Lesotho, Malaysia, Malta, Papua New Guinea, St Lucia, Sri Lanka, Britain and Tanzania are expected to attend on Nov. 12. Pakistan was suspended from the councils of the 53-nation group of mainly former British colonies in 1999 following a coup that brought General Pervez Musharraf to power. Placed under annual review, Pakistan was reinstated to full membership in May 2004 but has remained on the CMAG watch list ever since. CMAG was established in 1995 to deal with serious or persistent violations of Commonwealth rules on democracy. Its task is to asses the nature of the infringement and recommend measures for collective Commonwealth action aimed at the restoration of democracy and constitutional rule. To date it has met a total of 28 times, excluding special or extraordinary meetings. DEEP CONCERN McKinnon said on Saturday, the day the state of emergency was declared, that he was deeply worried by the events and calling it a serious setback for democracy. He said suspension of the country's constitution was a "matter of deep concern" and called for immediate reinstatement of the constitution and the rule of law. Musharraf declared the state of emergency citing threats to national security. But coming just days before the Supreme Court was to rule on his re-election as president, the move was widely seen as an attempt to stop the judges invalidating it on the grounds that he stood while still army chief. Hundreds of lawyers and opposition activists have been detained by police since Saturday, leaving the opposition parties in disarray. (Reporting by Jeremy Lovell; Editing by Matthew Jones)