The Financial Services Authority (FSA) has handed out a record £33.32m fine to JP Morgan in the latest sign of a tougher regulatory stance from the City watchdog.

The penalty, which was announced today (3 June), was handed out after JP Morgan failed to protect client money by keeping it with its own money for almost seven years between 2002 and 2009 following the merger of JP Morgan and Chase Manhattan.

Clifford Chance acted for JP Morgan on the matter, while the FSA was advised by its in-house legal team. The FSA requires institutions to keep client money separate from their own funds in segregated accounts with trust status to help protect money in the event of an insolvency.

The fine, which represents the largest yet handed out by the regulator, initially stood at £47.6m but JP Morgan received a 30% discount for self-reporting the issue and cooperating with the FSA. Prior to this, the largest penalty served by the FSA was a £17m fine handed down to Shell in August 2004 for market abuse.

During the seven-year period, the client money balance varied between $1.9bn (£1.3bn) in December 2002 and $23bn (£15.7bn) in October 2008. Had the bank become insolvent at any time during this period, this client money would have been at risk of loss, the regulator asserted. However, no clients suffered losses as a result of the error.

FSA director of enforcement and financial crime Margaret Cole said: "[JP Morgan] committed a serious breach of our client money rules by failing to segregate billions of dollars… for nearly seven years. The penalty reflects the amount of client money involved in this breach."

She added: "The FSA has repeatedly emphasised the importance of ensuring that client money is adequately protected. Despite being one of the largest holders of client money in the UK, [JP Morgan] failed to do so.

"This penalty sends out a strong message to firms of all sizes that they must ensure client money is segregated in accordance with FSA rules. Firms need to sit up and take notice of this action – we have several more cases in the pipeline."

The size of the fine will be seen as further evidence of a more robust stance from the FSA as it moves to head off criticism that it failed to regulate the City effectively in the wake of the credit crunch. The FSA won a high-profile victory in March this year when it secured the conviction of former Cazenove partner Malcolm Calvert on five counts of insider dealing.

However, the watchdog is expected to see its role substantially shaken up under the new coalition Government, though the Conservative-led administration has moved away from an earlier pledge to largely abolition the FSA.

One partner specialising in financial services regulation with a top 10 City law firm commented: "Wow. The size of the fine shows the seriousness of the offence. This is a big deal."

Taylor Wessing financial disputes head Shane Gleghorn commented: "This is a record fine that makes it clear that the FSA will deal harshly with anyone breaching client money rules and underlines the desire of the regulator to avoid a repetition of the kind of spectacular client money failings which occurred with Lehman Brothers."

He added: "Our regulatory partners have seen an increase in the amount of advice they give to clients regarding client money over the past year, which is perhaps understandable given that the FSA has established a unit to enhance and strengthen the FSA's capabilities in the area and has issued 'Dear CEO' letters on the subject this year. The size of the fine is likely to add to the awareness of firms that they should seek advice to make sure they comply."