Paula Dodds, Chair of the Metropolitan Police Federation, said: "Police officers across London today will be fighting crime, confronting armed and very dangerous criminals and tackling, deterring and detecting those who would do us all serious harm.
"18 Metropolitan Police will be assaulted on duty today.
"These very same officers will be disgusted to hear that the Metropolitan Police Commissioner thinks there are too many of them and that they are paid too much.
"Technology has its place in policing. But it must never replace the courageous police officers out there on the streets carrying out their difficult and dangerous role. The detectives who are painstakingly protecting the vulnerable and bringing people to justice.
"The current focus on funding for technology has gone too far. We need funding - and proper funding - for police officers who can keep us all safe 24/7.
"Police Officer pay is already around 20% behind inflation in the past 15 years so it's outrageous to hear Sir Mark Rowley - on a salary of nearly £300,000 a year - say that police officer pay has been "protected" at the expense of technology.
"Tell that to officers who are struggling to pay the bills. Or the 15% of officers who report missing meals due to lack of money. Or the one in three officers thinking of leaving because of their poor pay.
"We reiterate that technology has an important place in modern day policing but we must prioritise police officers.
"Cuts have consequences - police officer numbers are already on the way down... and the officers remaining are emotionally and physically exhausted.
"Protest after protest. Relentless day to day demand. Precious days off and time to rest and recuperate cancelled.
"We will be making these points clear to senior officers and politicians of all parties. We remind everyone what a previous Commissioner once said... you can't throw laptops at crowds."