The Chilean government's new plan to usher in private investment at a number of the country's lithium salt flats may stumble over unresolved details that will raise concerns for investors, mining executives and analysts said on Wednesday.

Industry players said they are seeking information on how contracts will be awarded by officials in the country that is the world's second-biggest lithium producer and are worried about pushback from Indigenous communities and environmental campaigners.

Chile in April will begin seeking proposals from private firms interested in extracting lithium, a key energy transition material used in electric vehicle batteries, from 26 salt flats not earmarked for state control, officials said on Tuesday.

The plan is one of the new planks of President Gabriel Boric's 2023 lithium policy mandating public-private partnerships.

The government will reserve two of its best salt flats, Atacama and Maricunga, for majority control through state-run copper miner Codelco, while progressing projects via state-run companies at another five salt flats.

The state-developed projects alone are expected to double Chile's output to about 500 000 metric tons of lithium carbonate equivalent by the end of decade, Mining Minister Aurora Williams said on Wednesday.

For the remaining 26 salt flats, officials will accept statements of interest through July.

Nearly 100 companies from a dozen countries have already approached the government to seek information about launching lithium projects, Williams said, including from the U.S. and China.

Yet, executives and analysts pointed out red flags in Tuesday's announcement they say could put a damper on new projects.

One concern is how the government will award lithium contracts in salt flats where mining concessions have previously been granted, which risks creating a kind of double ownership.

"It creates many potential conflicts, setting the stage for future judicial problems," said Sebastian Yang, a board member of Simco Lithium, which has a project in the Maricunga salt flat.

"This will pose a difficulty for attracting potential investors."

Chile's Mining Ministry did not immediately respond to a request for comment.

Jose Hofer, a lithium adviser at consultancy SC Insights, said other challenges that could curb investor appetite include required state partnerships, potential pushback from Indigenous communities and limits on extraction throughout a swath of the salt flats due to environmental protections.

"This over layering of policies and excess of state involvement has made Chile 'un-investable' in lithium," he said, noting that Argentina and Brazil will likely become more significant players compared to Chile over the next decade.

Companies must also grapple with a soft patch for lithium prices amid a slowdown in EV sales, which has changed the calculus for ensuring economically viable projects.

For Canada-based Wealth Minerals WML.V, moving forward with its lithium project in the Atacama salt flat will mean starting talks with Codelco over the terms in which the state-owned miner will take a majority stake, said executive director Marcelo Awad.

"We're optimistic and very interested in starting a negotiation with Codelco as soon as possible," he said.