Makoto Uchida, the CEO of Nissan, said Wednesday that the global chip shortage needs to be closely monitored as supply issues are yet to be fully resolved.

The Japanese car manufacturer announced in May that it expected to make half a million fewer vehicles in 2021 as a result of the chip shortage. It added that it hoped to mitigate the impact in the second half of the year.

“Knowing the current situation … we cannot be optimistic,” Uchida told CNBC’s “Street Signs Europe” on Wednesday. “I think this is day-by-day still.”

The chip shortage came about after a surge in demand coincided with the coronavirus pandemic. There’s also a shortage of factories making the older, less advanced chips that are used in cars.

Uchida believes the chip shortage situation will improve but he warned there are “many complexities” surrounding semiconductor suppliers as a result of the coronavirus pandemic.

“We need to carefully monitor that,” he said. “We need to anticipate because nobody knows what will happen in the coming months.”

Nissan swung to profit in its latest quarter and upgraded its guidance for the year on Wednesday.

While the chip crunch is likely to continue, Uchida said Nissan is positive about dealing with the issue.

“We are quite confident because in the first quarter we could minimize the impact of the semiconductor shortage through strategic management of inventory and parts procurement,” he said. 

Favorable conditions in the U.S. market and the price hike of used cars also contributed to Nissan’s latest results, he said.

There are signs that the chip shortage is starting to affect companies beyond the automotive and gaming industries.

Apple CEO Tim Cook said on Tuesday that the company is struggling to get its hands on all of the basic chips that it needs to power the iPhone and the iPad.