Undercover operations targeting shops selling knives to children will be stepped up in the next year.
Westminster Council plans to visit up to 100 shops during the next 12 months to combat the sale of knives to children.
Since April this year, 38 test purchases have been carried out, resulting in 17 sales to children under the age of 18.
Companies and shop staff who hand over the knives face a maximum £5,000 fine or six months in jail.
Other ways of tackling knife crime introduced by the council include providing more after-school and holiday clubs, increasing patrols by City Guardians to reassure residents and using Westminster's member of youth parliament (MYP) Ansar Patel as a figurehead for young people.
Westminster Council's cabinet member for community protection Cllr Daniel Astaire said: "Although Westminster doesn't have high levels of knife crime and antisocial behaviour, the impact of just one incident is one too many. For the first time, we've drawn up a specific knife strategy and created a dedicated multi-agency group to co-ordinate all reactive, preventative and educational programmes about youths and weapons."