President Yoon Suk Yeol called by phone his counterparts in Germany and Denmark Tuesday to provide an explanation for postponing his trip to the two European countries, according to his office on Wednesday.

Yoon asked German President Frank-Walter Steinmeier and Danish Prime Minister Mette Frederiksen for understanding for delaying his previously scheduled visit. Yoon had been set to depart Seoul this Sunday for a weeklong trip including a state visit to Germany.

Yoon told Steinmeier and Frederiksen that he had no other choice but to delay the visit to "focus on domestic affairs," the presidential office said, without elaborating on what the affairs were.

One issue that Yoon is dealing with is a crisis unraveling in the health care field here, as more than 70 percent of the country's trainee doctors, who are key to keeping hospitals running, have submitted their resignations to protest the government's plan to increase the medical school enrollment quota by 2,000 students each year starting next year.

According to the presidential office, both Steinmeier and Frederiksen "understood Yoon's stance" and would "welcome Yoon" any time he visits the countries.

Yoon's office stressed that the cooperation between South Korea and Germany in the field of security, cutting-edge technologies and cyber technologies will remain unperturbed despite him postponing his trip to Germany this week.

Earlier on Monday, the intelligence agencies of South Korea and Germany launched the second Joint Cyber Security Advisory to fight cyber threats from North Korea.

Moreover, Yoon reaffirmed the Comprehensive Green Strategic Partnership between Seoul and Copenhagen over the phone with his Danish counterpart. It added that the two countries will further strengthen the "green growth alliance" and cooperation in cutting-edge science and technology.

The presidential office on Feb. 14 revealed that the planned trip to the two countries would be postponed after carefully considering various factors, without explaining further.