Seoul city authorities have expanded subway operations after the Seoul city bus union launched an indefinite full‑scale strike starting Tuesday.

The city extended peak‑hour subway service by one hour in both the morning and evening to deploy additional trains, while late‑night operations were extended until 2 a.m. the following day.

Under the plan, congestion periods will run from 7 a.m. to 10 a.m. and from 6 p.m. to 9 p.m., with extra trains added during those hours. Last train departures at terminal stations will also be pushed back to 2 a.m., increasing total subway operations by 172 runs.

All of the city’s 25 district offices will additionally operate free shuttle buses to connect with nearby subway stations.

City officials said they would mobilize all available transportation resources to minimize inconvenience to commuters and urged the bus union to return to work promptly in consideration of the public.