"While our demand is strong, we have a lot of vehicle deliveries to catch up to in order to have a successful quarter," Musk wrote in the mail.
"Per my earlier email, if we execute well, Q2 will be an all-time record for Tesla vehicle deliveries and an awesome victory!!"
Tesla was on course to deliver a record number of cars in the second quarter, beating the 90,700 it sent to customers in the final quarter of last year, Musk said in an internal email last week.
The company, which has struggled to keep up with Musk's delivery promises, had on average produced 900 Model 3 cars per day last week, according to last week's email, bringing it closer to a target of 7,000 per week.
Musk in the latest email said he will start holding calls with Tesla's delivery teams around the world every two days in order to know "what's needed to accelerate our rate of deliveries."
Demand for Tesla's Model 3 sedan and other cars has moved to the top of investors' list of worries after the company reported slack first-quarter demand against a backdrop of U.S.-China trade tensions.
Tesla did not immediately respond to a request for comment.
News website Electrek had earlier reported about Musk's leaked email to the employees.
Tesla's shares closed up nearly 1% at $189.86. (Reporting by Akanksha Rana in Bengaluru; Editing by Sriraj Kalluvila)