The European Union's aviation safety authority will be "ready to react appropriately" against possible flight maintenance issues of the European operation of South Korean low-cost carrier T'way Air, which has recently been plagued by frequent delays due to aircraft maintenance issues, an agency spokesperson said Thursday.

T'way Air experienced four flight delay incidents last week alone, affecting hundreds of international passengers connecting South Korea with overseas destinations, including Japan and Thailand, due to maintenance problems.

They occurred as T'way is set to soon take over four routes connecting South Korea with major European cities -- Frankfurt, Paris, Rome and Barcelona -- from domestic industry leader Korean Air Co., as part of conditions set by the EU over Korean Air's envisioned merger with No. 2 player Asiana Airlines Inc.

T'way plans to begin operating flights to Paris as early as next month and gradually expand to the other three routes.

"Where necessary in the interest of safety, EASA will be ready to react appropriately," Vera Tavares, spokesperson of the European Union Aviation Safety Agency, told Yonhap News Agency via email when asked whether the agency plans to look into circumstances surrounding T'way's repeated maintenance issues ahead of its new European operations.

The spokesperson said EASA issues third-country operator authorizations to foreign air operators based on the confidence in the airline and the authority with jurisdiction "to execute adequate oversight over the operators that it has certified."

While noting that the agency cannot "replace the competent authority," it stressed that it "does not solely rely on the action taken by the foreign authority."

"(EASA) will monitor the further development as part of its obligation to perform continuous monitoring of TCOs," Tavares said, adding, "Ramp inspections performed at EU aerodromes are instrumental in this regard."

Tavares also said EASA has several options for enforcement measures within its TCO regulations, "including a possible suspension of the authorization," should the agency obtain evidence that the safety performance of an airline in question "continues to degrade."

Earlier this year, South Korea's transport ministry also found evidence that T'way used unauthorized parts in its in-aircraft heating and cooling systems during a special investigation. (Yonhap)