The plan for Apple senior vice president of Machine Learning and AI Strategy John Giannandrea to retire early next year comes after the tech giant stumbled in efforts to show it was not being left behind on the technology.

Giannandrea will serve as an advisor to Apple during his remaining time with the company, according to the iPhone maker.

"We are thankful for the role John played in building and advancing our AI work," Apple chief executive Tim Cook said in a post announcing the news.

Researcher Amar Subramanya has joined Apple as a vice president and will lead in "critical areas," including AI foundation models and machine learning, according to the company.

Subramanya was most recently a corporate vice president of AI at Microsoft, prior to that spending 16 years at Google where he was head of engineering for the Gemini digital assistant before leaving, Apple said.

Apple cited Subramanya's experience integrating AI into features and products as "important to Apple's ongoing innovation and future Apple Intelligence features."

Giannandrea joined Apple in 2018, heading the company's AI efforts. Apple early this year delayed the release of an improved Siri digital assistant and is now promising it for next year.

Meanwhile, Google, Microsoft, OpenAI and other tech rivals have been releasing ever-improved AI models and features in a fierce race to lead in the technology.

Apple has been under pressure to show it is not being left behind when it comes to artificial intelligence, with the potential to change how people engage with the internet and computers.

Cook cited AI as "central to Apple's strategy" and said Subramanya will bring "extraordinary AI expertise" to his role reporting to senior vice president of Software Engineering Craig Federighi.

"Craig has been instrumental in driving our AI efforts, including overseeing our work to bring a more personalized Siri to users next year," Cook said.

On a recent earnings call, Cook touted the latest Apple devices and the tech giant's custom chips and efforts to enhance products and services with artificial intelligence.