SEOUL: South Korea will be without in-form Tottenham Hotspur forward Son Heung-min in its crucial 2018 World Cup qualifier in China later this month.

Son, who scored a hat-trick on Sunday as Spurs thrashed London rival Millwall 6-0 to move into the last four of the FA Cup, is suspended for the March 23 game in the Chinese city of Changsa.

With South Korea returning to Seoul to face Syria five days later, national team coach Uli Stielike still included Son in his 24-man roster, announced Monday in Seoul.

The 2002 World Cup semi-finalist beat China 3-2 last September and sits in second place in Group A in the third round of qualification with 10 points from five games, one point behind Iran. There are five games remaining and the top two teams from the group qualify automatically for the World Cup in Russia.

"We will do our best to get the win in China and start the second half of the round on a high note," Stielike told a news conference in Seoul.

China, which has qualified only once for the World Cup, is struggling with just two points but is aiming for an upturn in results after appointing 2006 World Cup-winning coach Marcello Lippi in October.

To add extra tension to the match, it comes at a time when relations between the countries off the field are at a low point after South Korea agreed to cooperate wit the US on a missile defence system.

China has argued that the system is a threat to its national security and has hit back with a string of economic measures that include instructing domestic tour companies not to sell tour packages to South Korea.

"Outside factors will not have a bearing on the game." Stielike, who selected four China-based players in his squad, said. "We are just focusing on preparing as well as we can."

Last week, China refused a request from the Korea Football Association to charter a flight from Changsa to Seoul to allow its players more time to prepare for the subsequent game against Syria, forcing the KFA to make alternative plans.

"After China's decision, we asked a South Korean air carrier to reschedule the departure time of its flight, so our players can now return home quickly after playing the match on the road," said KFA spokesperson Cho Jun-heon.