"It would not be correct to apply historical cost savings to current quarter", tweeted Musk.
"The remainder of our discussions with suppliers are entirely focused on future parts price and design or process changes that will help us lower fundamental costs rather than prior period adjustments of capital expenditure project spending".
Concerns about Tesla's cash situation became top of mind once again on Monday when it was reported that the company had requested retroactive refunds from a handful of suppliers to improve its financial situation.
Tesla had $2.7 billion in cash on hand at the end of the first quarter and many specialists think it will need to raise money soon.
Tesla is spending about $1 billion a quarter as it ramps up manufacturing of the Model 3 sedan, a lower-priced vehicle that is key to Tesla's plans of becoming a major mass-market automaker.
Tesla did not immediately respond to a request for comment from CNNMoney.
In a memo to targeted suppliers, management framed the appeal as an "investment", an opportunity to ensure Tesla's continuation and, by extension, its ability to remain a parts buyer.
"I haven't heard of this being done before and I've been following the industry for 20 years, " he said.
Tesla shares have fallen sharply after it was revealed the electric carmaker is seeking refunds from some suppliers. He said it "could be an indication production is ramping". This could be a sign that Musk has to change his mind, Whiston said.
The leak comes as Musk continues to unnerve investors, with Tesla shares falling from a year high of $370 in mid June to around $301 on Monday.
The cost of insuring $100 of Tesla debt hit $6.58 around 10:30 am Tuesday, according to data from Bloomberg, amid fresh fears over Tesla's cash position.
An analyst at Baillie Gifford, Tesla's third-largest institutional shareholder, told the Journal the firm is "divided" on whether Musk is the right leader for Tesla. What's more, a recent teardown of the Model 3 suggests that Tesla's mass market EV might be far more profitable than initially anticipated. The company also has taken $1,000 deposits for Model 3 orders to help fund development and manufacturing, which established carmakers don't have to do.