The Alexandria City Council agreed unanimously last night to participate in a regional 911 emergency dialing system.The decision will bring a 911 emergency system to Northern Virginia as early as February, according to a phone company executive.

Residents of suburban Maryland and the District of Columbia already can make emergency calls -- to summon police, fire or ambulance assistance -- by dialing 911.

The city council's vote ended nearly a year of controversy in which Alexandria had blocked the desire of other Northern Virginia governments to set up a "basic" 911 system. Such a system requires regional cooperation; the council previously held out for a more expensive and effective electronic 911 system, which cannot be set up for at least two years.

Last night the council voted to join the "basic" system in expectation that the other jurisdictions eventually will participate in the electronic system. Mayor Charles E. Beatley Jr. remarked: "Let's say a little prayer our friends in other jurisdictions help us out."

After the meeting Vice Mayor Robert L. Calhoun criticized unnamed city staff members for "poor staff work" on the subject, which caused the council to delay a favorable vote until it could get additional information.