Ekstrom claimed the 2016 title in an ERS RX-built Audi S1 with four wins helping him to beat Johan Kristoffersson to the crown, and finished runner-up to his fellow Swede on a further three occasions in 2017, 2018 and 2020.
His last World RX appearances came with the Munnich Motorsport SEAT team at the Latvia double-header in 2021, and he didn't participate last season as the championship switched to full EV technology.
However, Ekstrom is no stranger to electric cars having won the inaugural ETCR championship in 2021, featured in the maiden season of Extreme E for Abt Cupra the same year, and contested the past two editions of the Dakar Rally with Audi's RS Q e-tron E2 which includes three electric motors.
Fresh from his fourth victory in the Race of Champions last month, Ekstrom will join Rallycross Promoter as its representative in all sporting matters relating to the world championship.
He explained that this would cover everything "from the format to commercial and sponsorship affairs and in broader terms, the overall product".
"I’m keen to bring the benefit of my experience to really strengthen the series at this important stage in its history," said Ekstrom.
"That means I’ll be working closely with the drivers, teams, circuits, partners and the FIA, as well obviously as Arne [Dirks, executive director] and the rest of the Rallycross Promoter team."
Ekstrom was inspired to get involved in motorsport by his father Bengt, himself a rallycross competitor, and said he was passionate about seeing the discipline succeed.
"Even though I didn’t start competing in rallycross myself until 2013, it is in some respects where everything began for me," he said.
"In its short nine-year history, World RX has already shown its potential to capture fans’ imagination in a way that few other disciplines are capable of doing.
"There’s no denying that for various reasons, it has been a tough few years, but everything I have seen since Rallycross Promoter took over [from IMG] and the start of the electric era convinces me that the best is yet to come.
"All the ingredients are there to attract new generations of fans and make this championship a real blockbuster success."
After launching its new era in 2022 with only eight cars contesting the majority of the season, Ekstrom added that an important priority is to attract more manufacturers to the championship.
He believes the series' sustainable credentials means it has "a trump card to play".
"If we want to get the manufacturers back in and more teams and sponsors involved – which is clearly one of the major goals – being more sustainable is the only way forward," the two-time DTM champion with Audi said.
"In the future, all motorsport will be judged on how sustainable it is; the time to act is now.
"That’s why World RX has such a trump card to play – it allows manufacturers and private teams to showcase their technological expertise without harming their green credentials. It’s win-win."
