The timing of the report could be a sign that the gradual expiration of federal tax credits for Tesla vehicles is hitting demand for the sedan, said CFRA analyst Garrett Nelson in a note published Wednesday. The reduction in the tax credits began this year.

A report saying that Tesla might be starting a leasing program for its Model 3 sedan could be a bad sign for investors in the electric car maker, according to one analyst.

"While TSLA has meaningfully driven down vehicle unit costs in recent quarters, we have growing concerns regarding top-line results due to combination of moderating sales volume, price reductions and mix," Nelson said. "Looking past the near term, we expect TSLA to face significantly increased EV competition starting with the 2021 model year."

Tesla responded to a report from news site Electrek published on Tuesday saying the electric vehicle manufacturer is planning a leasing program, but that it has not finalized the dates when it will begin.

"This is simply an internal document to ensure teams are prepared for when we eventually introduce a leasing option to customers," said a statement from Tesla send to CNBC, referring to the email referenced in the Electrek report. "No decision has been made about when Model 3 leasing will be available, but it will definitely be after the dates outlined in this document."

CEO Elon Musk also said on the company's fourth-quarter earnings calls that Tesla might wait until later this year to start a program.

"We've been reluctant to introduce leasing on Model 3 because of its effect on GAAP financials," Musk said on the call. "It is worth noting that demand to date is with zero leasing. Obviously, leasing is a way to improve demand, but it makes our financials looks worse. So we're not wanting to introduce that right away. We'll introduce it sometime later this year probably."

Tesla already offers leases on its other models, and it is common for customers to lease vehicles in the premium end of the car market.

Several manufacturers are either already selling electric vehicles or planning to release new models in the next few years. Some are aimed at the higher end of the market, where Tesla's vehicles are priced, especially the full-size Model S sedan and Model X SUV.

Musk billed the Model 3 as a relatively affordable electric car, and initially Tesla intended to sell them at a starting price of $35,000, much lower than the current price. Competitors are eyeing that end of the market as well.