SEOUL (Yonhap) -- Subway and bus fares in Seoul and its adjacent cities will likely jump by 10 percent in the second half of the year, adding to the already heavy financial burden on households under inflationary pressure.

The Ministry of Public Administration and Security announced a guideline for local governments' management of public service fares on Thursday, allowing them to marginally raise mass transit service fares while leaving most other fares in place during the second half to stabilize prices.

The guideline required local administrations to decide the rates of subway and bus fare hikes based on the annual average rate of consumer price hikes since the last time the fare was raised.

For instance, municipal governments of Seoul, Incheon and Gyeonggi Province were allowed to raise fares within the limit of

10.4 percent, according to the ministry.

The basic subway and bus fares for adults in the capital area are currently set at 900 won (US$0.8) and 1,000 won each, and were both last raised in 2007.

The fares, if changed, will be frozen for the next two to three years, it said.

Ministry officials said the public service fare hikes are inevitable because the long-term accumulation of deficits and rising production costs have aggravated management conditions of the operators.

Local governments have injected a total of 2.35 trillion won (US$2.19 billion) last year alone to make up for the losses incurred by the inner-city bus, subway, and water and sewage operators, they said.