Thirty Meter Telescope officials insisted Monday that news of their Canary Islands building permit application does not mean they’re giving up on Hawaii.

TMT Executive Director Ed Stone said submitting the application is just another step in the project’s ongoing effort to secure a “Plan B” site on La Palma island if it becomes impossible to build on Mauna Kea.

“This process has been ongoing since 2016,” Stone said in a statement Monday. “Maunakea remains the preferred site for TMT.”

Canary Islands Astrophysics Institute Director Rafael Rebolo told The Associated Press on Monday that he received a letter from the TMT consortium saying its governing board recently decided “to proceed with the request to seek a building permit” on La Palma.

In an interview, Rebolo said he understands that Hawaii remains TMT International Observatory LCC’s first choice.

“Our position is that we are here if the TMT project needs us,” he said.

News of the La Palma application comes as project foes appear to be firmly in control of the Big Island mountain on which TMT officials hope to construct the $1.4 billion project.

Protesters continue to maintain their positions at Mauna Kea Access Road in the fourth week of a protest aimed at preventing heavy- equipment crews from climbing the mountain to start construction on the next-generation telescope.

Protest leaders welcomed the building permit development.

“There’s lots of good science to be done from the Canary Islands,” said Kea-loha Pisciotta, a former Mauna Kea astronomy worker who has led the legal challenge against the TMT for years. It would “be a win for everyone.”

Kaho‘okahi Kanuha said he hopes the telescope builders make the “right decision” and move their project to the Canary Islands.

“We remain committed to protecting Mauna Kea from further desecration, no matter how long it takes,” he said.

But if the building permit is good news for the protectors, there may be some bad news as well.

A Canary Islands environmental group Monday declared that it was ready to challenge the TMT in court if it continues to pursue construction on La Palma.

The organization known as Ben Magec, part of the Spanish “Ecologists in Action” federation of environmental groups, said it had already achieved its first victory, persuading a judge recently to revoke the 75-year agreement that set aside nearly 25 acres of land for construction of the telescope.

“This means they will have to start the procedure from the beginning, causing a substantial delay,” a news release said.

Local TMT officials could not confirm the legal ruling Monday, but said they were aware of the court challenge.

The Ben Magec organization couldn’t be reached Monday, but its news release said a judge overturned the concession because of violations of European environmental laws and due to a miscalculation of the value of the concession, which had called for an annual payment from TMT of $1,250.

“If they insist in getting authorization to build the TMT in this legally protected area on La Palma, each step will lead to additional legal action on our part. We will not hesitate to take it to the Supreme Court of Spain because we are convinced that, in relation to the TMT, public administrations are making decisions that are in conflict with Spanish and European Laws,” the release said.

When it comes to the Canary Islands, one should not assume TMT will sail smoothly by administrative and legal obstacles and that the people and local organizations will not oppose it, the organization warned.

“We have no less reason or less determination than the Hawaiian TMT opponents,” the Ben Magec release said.

La Palma, an island the size of Molokai, has experienced the development of astronomy “without respect for the people and for the natural and cultural values,” the group said. “It has cost us a notable part of our nature and we have lost archaeological sites that were very important for the understanding of the culture of our aboriginal ancestors.”

There’s a growing feeling, according to the organization, that “our mountain has already exceeded the capacity to house more telescopes and that we have already paid a high price for astronomical science. We are strongly opposing a project that will have a very negative impact on a unique natural area of high value that is part of the European Natura 2000 network, one of the world’s largest networks of protected natural areas.”

Observatorio del Roque de los Muchachos is home to 14 telescopes, including the 10.2-meter Gran Telescopio de Canarias, and was recently tapped as the site of the Cherenkov Telescope Array, which is set to become the largest ground-based gamma ray detection observatory in the world.

The Associated Press contributed to this story.