(Reuters) -Rivian posted its first drop in quarterly revenue on Thursday since the electric vehicle maker went public three years ago, partially hurt by the shortage of a component.

"We weren't able to build all the products and the mix of products that we planned and so that affected us on the demand side and on the revenue side," CEO RJ Scaringe told Reuters in an interview.

Due to the shortage of a part used in the drive unit, Rivian last month slashed its full-year production forecast to between 47,000 and 49,000 vehicles, from its earlier projection of 57,000 units.

This would mean a decline in annual production from last year for the Amazon.com-backed company. However it expects deliveries to grow to between 50,500 and 52,000 vehicles in 2024, from 50,122 units last year.

Revenue in the third quarter slumped 34.6% to $874 million, missing analysts' average estimate of $989.6 million, according to data compiled by LSEG.

EV startups like Rivian and Saudi PIF-backed rival Lucid have been burning cash as they grapple with ballooning costs to ramp up production to take on market leader Tesla.

Loss-making Rivian is set to post its first adjusted core profit only in the third quarter of 2026, according to LSEG data and analysts have said that the company may need to raise funds in the next two years to shore up cash balances.

It posted a net loss of $1.1 billion for the July-September quarter, compared with a loss of $1.37 billion a year earlier.

In the quarter ended Sept. 30, Rivian said its cash and cash equivalents were $5.4 billion, compared with $7.86 billion in the fourth quarter of last year.

Rivian also announced a multi-year supply deal for batteries with LG Energy Solution's Arizona subsidiary for its R2 midsized SUV.

The agreement will help the EV maker stick to the domestic manufacturing requirements as part of the Biden Administration's Inflation Reduction Act, which provides incentives for EV buyers.

"We're closely analyzing a variety of outcomes that could play out with the change in administration," Scaringe told Reuters regarding Donald Trump's election victory and potential alterations of policies around EVs.

Shares of the Irvine, California-based company rose nearly 2% in extended trading.

Separately, Lucid beat Wall Street expectations for third-quarter revenue and reiterated its annual production forecast.