The City’s watchdog came under fire on Thursday for its controversial plans to change stock market listing rules, in order to allow Saudi oil firm Aramco to list on the London exchange.

The Financial Conduct Authority (FCA) is proposing to change current listing rules, adding a new category that would relax the requirement for ‘premium’ companies, including the Saudi state-owned Aramco, to list on the London Stock Exchange.

Global markets are fighting over who will win the listing of Saudi Arabia’s oil firm Aramco, which is thought to be the world’s biggest flotation with a value of $2 trillion. Aramco are aiming to float a 5 percent stake on the market, a far smaller portion than the 25 percent normally requested by London listing rules.

However, critics have called the idea of bending the rules “inappropriate”. Ashley Hamilton Claxton, corporate governance manager at Royal London Asset Management, told CityAM:

“It looks like the FCA is consulting on amending the existing listing rules to accommodate the peculiarities of one company, which is not a very effective strategy for regulating the market as a whole. If the proposals in this consultation document are implemented, it will be bad news for London and will reverse the progress we have made in recent years to uphold strong governance and protect minority shareholders.”