Belgium assistant manager Marc Wilmots has warned Chelsea striker Romelu Lukaku that his place in the national team will be under threat if he isn't playing regular football, reports insidefutbol.com.
The 18-year-old has made just six first-team appearances for the Blues since arriving at Stamford Bridge from Anderlecht last summer, spending the majority of the season on the fringes of Andre Villas-Boas' side.
"Obviously if a player does not play for his club, it is difficult to select him for the national team," said Wilmots. "You need rhythm, games and confidence which, in September, will be crucial.
"The decision is his, but I advise him to find playing time. Now, if he is sure he'll play at Chelsea - it is he who must make the choice."
Lukaku wasn't even on the bench for the 3-0 victory over Bolton Wanderers at the weekend, adding to speculation he could leave on loan.
Stoke City and Bolton have both been credited with an interest in taking him on a short-term deal, with a view to giving him more experience of the Premier League.
Wilmots, who has served as Belgium assistant since 2009 and has been widely tipped as a future national team boss, feels it's important for the talented teenager to be playing regularly ahead of the 2014 World Cup qualifying campaign.
"It is difficult for us if he does not play with his team," he added. "We support everyone, but if they don't play it becomes difficult for us to select them for the national team."