Unionized pilots at Asiana Airlines announced that they will go on strike from July 24 after failing to narrow differences with management in wage negotiations.

According to the union on Friday, they are kicking off a work-to-rule protest over a breakdown in the fourth round of talks that ran through Thursday, with a strike beginning the last week of the month.

In the protest, pilots will engage in tactics such as refusing to fly over aircraft defects and using more fuel through measures like reducing the plane’s speed in order to inflict financial damage on the company.

One union official said that differences with the management side have not been bridged despite their first round of work-to-rule protests.

The official said the pilots express regret for inconveniencing the public during the summer travel season, but promised to make an effort to minimize disruptions as much as possible while trying to persuade the company to change its stance.

By law the nation's aviation companies are required to maintain over 80 percent of the workforce for flights on international routes and 50 percent for domestic routes even during strikes.

The previous work-to-rule protest that began on June 7 caused 28 flight delays as of July 3.