(CNN) -- The National Hockey League canceled more games on Monday due to a labor dispute that has wiped out the season so far.
Negotiations in recent days with federal mediators failed to resolve differences in contract negotiations aimed at ending the lockout of unionized players.
NHL Deputy Commissioner Bill Daly announced the cancellation of games through Dec. 30.
The NHL first canceled preseason games and now has called off the first half of the schedule.
The door, however, still is open to a possible deal to salvage the second half of the season and the Stanley Cup Playoffs.
A total of 526 games, nearly 43 percent of the season, were scheduled from the start of the regular season on October 11 through December 30, the NHL said.
A similar labor dispute canceled the entire NHL season eight years ago.