Farmers in South Canterbury are refusing to Transpower on their land to upgrade power pylons until they are given compensation.
The national grid operator is in the region this week and needs access to the farms to upgrade the line that supplies much of the power to Christchurch.
But farmers say they will not let Transpower carry out the work until they receive fair compensation for the use of their land.
Federated Farmers' electricity spokesperson Philip York says Transpower is expanding the amount of land occupied by its towers and needs permission to do so.
"If they're going to take land that they're not entitled to, then they're trespassing. Our legal people say that in that case, (farmers are) entitled to keep them off the property until they negotiate an easement, or go and get a court ruling."
Mr York says Transpower must negotiate access with the land owners.
Farmer Miles Anderson took advantage of his legal right to delay Transpower for a fortnight to carry out farm management. He is determined that he will not back down.
"There are landowners up and down the country that are going to have similar works needing to be done over the next four or five years, and they will feel the same.
"It's going to come to a point where the work's going to be held up for that long that maybe Transpower will sit down and talk to the landowners seriously."
Transpower says it has a legal right to enter properties to do maintenance. It says it has had several constructive discussions with farmers and is confident that arrangements can be made.