The announcement comes just days after Bumi, the Indonesian venture that was
listed on the London Stock Exchange following a reverse takeover, launched
an inquiry into $500m (£309m) of “potential financial irregularities” in its
Indonesian operations.

It also follows a similar step to increase investor protection taken in
December by the FTSE Group, which runs the blue-chip FTSE 100 index. At the
end of last year, FTSE tightened entry requirements for companies in its
indices, requiring that they have a minimum free float of 25pc. That move
was to ensure minority shareholders have more of a voice.

John Hammond, head of capital markets partner at Deloitte, said: “These
changes reflect the FSA’s commitment to evolving the rules to maintain
London’s reputation as the safest listing regime in the world.

“However, the recently announced Department of Business-London Stock Exchange
proposals to create a new market for technology and growth companies show
that London is also serious about offering a flexible listing regime that
provides different routes to market for companies and different levels of
investor protection, rather than a one size fits all approach.”