UN Secretary General Ban Ki-moon on Tuesday said he was struggling to stay neutral as his home team South Korea brace for their World Cup opener against Russia.

"That's a very delicate, sensitive question for me," the UN chief told reporters, chuckling, when pressed on where his loyalties lie. "I may not hide my own sentiment and support for the Korean team. But as secretary general, it would be very important that I need to be impartial. I'm supporting all the teams who are participating in the World Cup," he insisted.

"But you should know that at the same time, when the Korean team is competing with any other team, starting with Russia today, you may expect that my heart may beat much faster than normal times," he added. South Korea's Group H game against Russia in Cuiaba kicks off at 6:00 pm (2200 GMT) on Tuesday. The Taeguk Warriors became Asia's first ever World Cup semi-finalists when they co-hosted the 2002 edition with neighbouring Japan.

But their fortunes have taken a nose dive since those heady days and, while they are at their eighth consecutive World Cup, they struggled in qualifying, squeaking home only on goal difference. They are hoping that their youthful side will make the difference against the Russians, who under Italian icon Fabio Capello coasted to their first World Cup appearance since 2002. Ban said he had found a way to maintain his UN impartiality and avoid match-day stress into the bargain.

"Just to keep my neutrality, I decided not to watch the game. I'll get the report from my staff early tomorrow morning," he said. "I wish all the best to all the teams. Sport has extraordinary power to spontaneously unite the people," he added.