NELIGH, Neb. (AP) — Several hundred additional tickets are available for this weekend’s Willie Nelson and Neil Young concert organized by opponents of the proposed Keystone XL pipeline.

Organizers said Thursday that 500 additional $50 tickets would be sold on their www.BoldNebraska.org website and 200 more will be offered in Antelope County near where the concert will be held Saturday.

Previously ticket sales were capped at 7,000, but the farmer hosting the event cleared more space in his corn field.

The TransCanada Keystone XL pipeline would carry oil from Canada south to the Gulf Coast.

Pipeline critics worry it could contribute to pollution and contaminate groundwater.

TransCanada says the pipeline would be built with advanced safety features. The southern leg of the pipeline between Oklahoma and Texas is already operational.