The prestigious opera house La Scala in Milan has become embroiled in offstage drama of its own, with its boss under fire over negotiations to the Saudi Arabia culture minister, Badr bin Abdullah bin Mohammed bin Farhan Al Saud, become a member of the board.

Alexander Pereira, the Austrian chief executive and artistic director credited with bringing in more sponsors and creating a healthier balance sheet since his appointment in 2014, said the new board member would bring in an additional €15m (£12.8m) over the next five years.

Pereira said that the money would either be paid by a Saudi individual or come via a private company or bank.

“It’s a great opportunity,” Pereira said. “I’ve discussed it with Giuseppe Sala [the mayor of Milan] and Alberto Bonisoli [Italy’s culture minister], who has met his counterpart. Such economic opportunities don’t come by every day.”

But his negotiations have been described as “unscrupulous” by some board members, who called for the Italian government to intervene in the “complex and delicate” issue.

“The [negotiations] are an entirely personal initiative,” the members were quoted in the daily Corriere della Sera as saying. “At this moment Saudi Arabia does not stand out for its democratic balances.”

Maurizio Gasparri, a politician with Silvio Berlusconi’s Forza Italia party, has also raised the matter in parliament. He criticised Pereira for endeavouring to take money from a country that “does not respect fundamental human rights”.

“Recent dramatic events offer terrible signs, with Saudi Arabia accused of troubling incidents,” he added. “Our government also has the duty of defending the history and identity of La Scala.”

Pereira argued that only one board member was against the move, which will be discussed at a meeting on 18 March.

Prince Badr, a member of the Saudi royal family who was appointed culture minister last June, visited La Scala on 8 December to mark the beginning of the opera season.

In late 2017, he was revealed to be the mystery buyer of Leonardo da Vinci’s Salvator Mundi at Christie’s in New York. Fetching $450.3m (£341m), it was the most expensive painting sold at an auction.

Saudi Arabia has disputed reports he was acting as an intermediary for the crown prince, Mohammed bin Salman, instead saying he was acting on behalf of Abu Dhabi.

The painting is expected to eventually go on display at The Louvre Abu Dhabi.

Pereira, who is eyeing a second mandate after his term ends in February 2020, said that he is also working on bringing a concert version of Giuseppe Verdi’s opera, La Traviata, to the Saudi Arabian capital of Riyadh. Meanwhile, the Saudi royal family would like a music and dance conservatory, slated to open in Riyadh in September, to be managed by La Scala’s academy.

“Creating an academy in a country without musical education, where dance was banned, would also have an important value for Italy. And this is a project that France wanted to take control of,” said Pereira.