San Francisco Mayor Ed Lee announced the creation of a new agency on Thursday to oversee short-term rentals like those arranged by Airbnb, which matches people wishing to rent out all or part of their homes to temporary guests. The new department, the Office of Short-Term Rental Administration and Enforcement, will manage rental applications as well as coordinate efforts to pursue violators of the city's laws and complaints. The move comes roughly a month after a city committee moved to limit the length of stays for short-term rentals, amid concerns from opponents who say they may drive up prices for long-term renters. Lee said in a statement that while the rentals generate revenue for residents in the notoriously expensive city and promote tourism, local regulations need to be followed "to protect our housing supply and neighbourhood character." The new agency is the latest step in regulating the rentals for Lee, who last October signed an ordinance requiring short-term renters to prove they live in the listed dwellings most of the year and to pay hotel taxes. His office said city regulators this week sent out 15 violation letters for some 70 units in the city. San Francisco officials have estimated there are some 5,000 listings in San Francisco on Airbnb and another 1,200 can be found on vacation rental website VRBO. The city's Board of Supervisors is set to vote on July 14 on short-term rental measures including one that would limit hosts to renting accommodation to no more than 60 days a year, down from 90 currently. Residents can legally rent out their apartment or home for periods of less than 30 nights with a valid registration, according to Lee's office. Airbnb has grown quickly and is valued at far more than US$10 billion, with analysts assuming it can overcome any major regulatory backlash. The company did not immediately respond to a request for comment on the agency. Santa Monica, a prime tourist destination in the Los Angeles area, approved restrictions in May on short-term home rentals. Other state and local governments have taken similar steps. In New York, officials have struggled to enforce rules that limit short-term rentals.