The group has 12 trains on order with France's Alstom, with which it is aiming to introduce 20 daily return services between London, Paris, Brussels and Amsterdam, starting in 2030 and adding 7.5 million seats a year.
Last week, the Office for Road and Rail confirmed Virgin's fleet of 300km/h trains will be maintained at London's Temple Mills depot, alongside Eurostar.
Virgin said its entry would seek to "reimagine cross-Channel travel" by bringing its distinct brand of customer experience to the sector, which it said would "draw on a proven playbook" and take cues from Virgin Atlantic, Virgin Voyages and Virgin Hotels.
This includes pre-departure and onboard social spaces inspired by features and learnings from its Virgin Atlantic Clubhouses (airport lounges), a food and drink offering influenced by Virgin Voyages, and seating informed by Virgin Hotels' focus on comfort and design.
In addition, passengers will be able to earn Virgin Points through existing Virgin Red memberships, which can be spent on future journeys, flights, cruises, hotel stays and experiences.
Ambitions, Virgin has said, include exploring how its rail and airline networks can work together more closely to make it easier for Virgin Atlantic passengers arriving into London to continue their journeys to France and mainland Europe by rail.
Virgin has also promised to build accessibility into its rail operation "from the outset" and to draw on its 20 years' experience operating trains on the UK's West Coast Main Line between London, Birmingham, the North West and Scotland as Virgin Trains.
Josh Bayliss, Virgin Group Chief Executive, said the group had a "proud history" as a rail operator, and more than 40 years' experience across travel and hospitality. "This time, we’ll be connecting London with some of Europe’s greatest cities and giving passengers a distinctive new choice in cross-Channel travel," he said.
"Virgin has always thrived on challenging the status quo and aimed to provide our customers with a great experience. We’ll bring the same approach to the cross-Channel route, making the journey something to look forward to as much as the destination."
Bayliss added he was confidence Virgin's entry into the cross-Channel rail market would ensure more journeys between the UK and Europe are made by rail.