Jonathan Howell could walk away with shares and options of up to £10m (€14.5m) in the London Stock Exchange after unexpectedly quitting as finance director today, just a week after landing an expanded role when the exchange completed its takeover of Borsa Italiana.

Howell, who has worked at the LSE for 11 years and became finance director in December 1999, will leave the UK exchange at the end of January to take a similar role at Close Brothers early the following month, according to statements to the stock market by both companies this morning.