• Generali Stadium will have 71,500-seat capacity

• Inter fans protest the plans outside gala event

Internazionale and Milan have unveiled plans for their new Generali Stadium, which will replace the shared San Siro venue from the 2031-32 season.

The stadium, sponsored by Generali – Italy’s largest insurance company – will have a capacity of 71,500 seats and is expected to cost the two clubs €1.2 billion (£1bn). The plans were revealed at a gala event at Milan’s Castello Sforzesco on Thursday – but some fans in attendance voiced their opposition to San Siro being demolished.

Shortly before the briefing began, a group of Inter fans walked into the courtyard of the castle and unfurled a banner reading “you will never extinguish the lights at San Siro,” and chanting “hands off San Siro.” Work on the new stadium is set to begin in 2028, on the site of the existing 75,000-capacity venue.

The Generali Stadium will be shaped “low in the body, and rises up at either end” behind the goals, architect Norman Foster said. David Manica, a stadium specialist who collaborated with Foster on the project, added that the steep-sided design aims to bring fans as close to the pitch as possible.

“The most important thing that we realised when we designed this project is that San Siro is a feeling,” Manica said. “It’s more than a building, it’s a feeling … we brought all the seats as close as possible to the field. They could not be any closer, it’ll actually feel as though you’re sitting on the grass.”

The stadium will also be capable of hosting NFL international games, rugby matches and concerts. Milan and Inter paid €197 million (£165m) to acquire the current San Siro stadium and its adjacent parking arenas. The current ground will be largely demolished once construction work nears completion.

Also known as the Giuseppe Meazza Stadium, San Siro opened in 1926 and is the largest sports stadium in Italy. It is considered to be one of European football’s most iconic venues, but requires extensive modernisation despite undergoing a number of renovations during its lifespan.

The Generali Stadium could be used as a venue for Euro 2032, which is being jointly hosted by Italy and Turkey. Foster and Manica previously worked together on the new Wembley Stadium, while the architect’s Foster + Partners firm also designed the plans for Manchester United’s proposed new 100,000-capacity home.

• Additional reporting from Associated Press