Hyundai finished on a 19% high in Seoul, it’s best performance in the 21st century, according to data provider Refinitiv, CNN reports. The surge in the stocks has been attributed to the South Korean automaker’s long-rumoured collaboration with Apple on a car project.

Hyundai (HYMTF) and Apple have been in early stage and nothing has been decided,” Hyundai Motor said in a statement.

The collaboration is based on Apple and Hyundai’s common interest in electric, self-driving cars. According to a report by Reuters, Apple aims at producing a passenger vehicle by 2024, CNN reports. A Bloomberg report last week, without naming any sources, said that the company has already begun early development work on an electric vehicle.

Hyundai on the other hand announced that it would join the race to build such vehicles. The car manufacturer last October said that ‘it plans to invest 41 trillion won ($37 billion) into future mobility technology by 2025 — a commitment that puts it on par with major players like Volkswagen’.

“We believe Apple is in the early stages of talks and looking at a handful of strategic partnerships and collaborations globally with existing auto makers on the [electric vehicle] front, with Hyundai on the radar,” Wedbush analyst Dan Ives wrote in a research note published shortly after reports about the joint-project first broke.

“Self-driving cars are probably fairly far off for Apple given safety and regulatory issues. But electric cars are what could ultimately be a trillion dollar opportunity globally over the next decade,” he added

“It’s a smart strategic move for Apple to dive into the deep end of the pool on this new age of [electric] vehicles,” Ives said.

However, Apple hasn’t issued any comment yet.