US pharmaceutical company Moderna Inc (Nasdaq:MRNA) has delayed its late-July 2021 vaccine shipment schedule for South Korea to August 2021 due to supply problems that will affect other countries waiting for its vaccine doses, Reuters news agency reported on Tuesday.

Jung Eun-young, head of the vaccine procurement team of South Korea, said that the supply issue is linked to the vaccine manufacturing process involving Swiss contract drugmaker Lonza (SWX:LONN) and a Spain-based company which does bottling work for the Moderna vaccine.

"This means the production-related issue does not only affect South Korea. Rather it is a common problem for countries that receive the volume from the manufacturing site," Jung was quoted as saying during a news conference.

South Korea has a contract for 40 million doses of the Moderna vaccine, of which about 1.1 million have already arrived.

South Korean officials stated that the Moderna COVID-19 vaccines scheduled to arrive in August 2021 remained on schedule, adding that a detailed shipment plan would be made public once finalised.