Scotland Yard is to review its policing of violent demonstrations after the G20 protests to see if London needs harsher, European-style methods that could include the use of water cannon.

Sir Paul Stephenson, the Commissioner of the Metropolitan Police, said that they would look at the more robust tactics used by other European police forces.

In an interview with The Times to mark his first 100 days in office, Sir Paul also said that a failure to merge smaller police forces had left many unable to cope with serious and organised crime.

Sitting in his large, corner office at Scotland Yard, Sir Paul admitted that he had had a “tricky” start as commissioner after publicity surrounding the incompetency of officers involved in two rape trials and the policing of the G20 summit, which was followed by the death of Ian Tomlinson, a newspaper vendor.

The public dismay over the policing of the demonstration has led to four separate investigations by the Independent Police Complaints Commission into allegations of police brutality. Sir Paul has also called for a review of public-order tactics by Denis O’Connor, HM Chief Inspector of Constabulary.

The Met was also criticised for containing demonstrators for hours with its controversial “kettling” tactic.