New Zealand First leader Winston Peters will meet with Pike families and supporters in Greymouth on Sunday as he continues to push for a re-entry into the mine.
"When the event happened the Prime Minister said they would go to the ends of the earth to find out what happened for these people. They have gone back on that," Peters told the Herald.
The Government is under renewed pressure from Pike River families to prevent state-owned coal miner Solid Energy from permanently sealing the mine on the South Island's West Coast and preventing re-entry to its drift.
The families have cited a report from international mining experts that said the mine could be safe to re-enter and that a new independent entity should be set up to oversee the project.
The mine has been closed since November 2010 after a gas explosion killed 29 workers.