Montreal-area mayors are joining forces and seeking to join a lawsuit aimed at overturning Canada Post's decision to reduce home delivery.

The mayors of Montreal, Laval, Longueuil and surrounding suburbs want in on the lawsuit filed by the union that represents employees at the Crown corporation.

The mayors held a news conference this morning and say Canada Post's decision was made without consulting municipalities and will hurt large numbers of seniors and people with reduced mobility.

Canada Post has said it is committed to moving ahead with its plans to gradually reduce home mail delivery and install community mailboxes despite court challenges and calls for a moratorium by some mayors.

It says it has no choice but to go that route because of a continuing drop in letter volume.

Canada Post has stated it is ready to defend its position all the way to the Supreme Court.