Elon Musk, the CEO of electric car company Tesla Motors, is reportedly readying to fire executives working under the company overseas after weak sales figures in China reported that only 120 of its vehicles were sold in the country last month.

The information was acquired by Reuters from sources that chose to remain anonymous due to the sensitivity of the issue.

The number of Tesla vehicles sold in China in January, which is far below the aggressive targets set by the company, casts doubt on the ambitious plans of the company to expand globally.

Musk previously set expectations that sales in China would reach levels seen in the United States by as early as this year. However, two top managers of the company in China already left last year.

Share prices of Tesla decreased by 7 percent on Jan. 13 after Musk revealed that sales in China have been "unexpectedly weak" for last year's fourth quarter.

"We'll fix the China issue and be in pretty good shape probably in the middle of the year," said Musk.

However, sources revealed that Musk was less courteous in an internal e-mail sent to managers late last month. The Tesla CEO threatened to fire or place country managers on demotion if the managers are "not on a clear path to positive long-term cash flow," said the sources that saw the e-mail.

Musk added that company managers that were underperforming may be asked to leave Tesla Motors or to assume more junior roles within the company.

Tesla has not issued a comment regarding the authenticity of Musk's e-mail to managers to Reuters, which was sent a transcript by one of its sources.

China remains a significant focus of the expansion strategy set by Musk, though results have drastically fallen short of expectations. Musk previously said that the company is planning to increase annual production of electric vehicles from an expected 50,000 units in 2015 to an expected 500,000 units by 2020, with China and the United States as the largest markets for the electric cars.

Replacements in the executive board have been initiated due to lagging China sales, with Veronica Wu, the manager in China for Tesla Motors, leaving the company in the middle of December last year. Wu's predecessor, Kingston Chang, left his post in March 2014.

Factors that have caused the lower-than-expected sales, in addition to the departing executives, include the slow development of the company's retail network in China.