Violators will be fined 50,000 won ($45), the office said, noting an enforcement team of 18 civil servants will stroll up and down the streets from 9 a.m. to 10 p.m.

Seoul and South Korea as a whole have stepped up efforts to discourage smoking in public areas.

At present, people caught smoking within 10 meters of a subway entrance in Seoul are slapped with a fine of up to 100,000 won.

The Seocho district's smoke-free zone is currently restricted to the vicinity of Gangnam Station, one of the capital's busiest at the center of Gangnam-daero. Earlier in March 2012, the Gangnam Station area became the nation's first no-smoking street.

A recent poll of 619 pedestrians on Gangnam-daero found over 80 percent of them supported the expansion of the no-smoking zone to the entire boulevard, officials said, adding the move is expected to reduce second-hand smoke as well as the smoking rate. (Yonhap)