Lukaku sustained a thigh injury in training at the end of last month, causing him to miss a derby defeat to AC Milan and UEFA Champions League fixtures against Bayern Munich and Viktoria Plzen.

The striker, who is Belgium's record goalscorer with 68 goals in 102 senior caps, also appears doubtful for the Nerazzurri's Serie A tussle with Udinese on Monday (AEST), prompting Martinez to act with caution when selecting his squad for games against Wales and Netherlands.

"Romelu is making good progress, his recovery is going in the right direction," Martinez said.

"He will probably return to Inter within a week, not calling him was a prudent choice.

"With Romelu it was important not to risk, because a relapse with an injury of this type would be very risky in view of the World Cup."

Milan's Divock Origi is also absent from Belgium's latest squad after failing to make a Serie A start since completing his move from Liverpool, although fellow Rossoneri newcomer Charles De Ketelaere is in.

Anderlecht defender Zeno Debast is the only uncapped player selected by Martinez, who has picked an experienced 30-man party in a bid to make up a three-point gap to Netherlands at the top of Group A4.

Belgium squad: Thibaut Courtois (Real Madrid), Simon Mignolet (Club Brugge), Koen Casteels (Wolfsburg), Matz Sels (Strasbourg); Jan Vertonghen (Anderlecht), Toby Alderweireld (Antwerp), Thomas Meunier (Borussia Dortmund), Jason Denayer (free agent), Dedryck Boyata (Club Brugge), Timothy Castagne (Leicester City), Arthur Theate (Rennes), Brandon Mechele (Club Brugge), Wout Faes (Leicester City), Zeno Debast (Anderlect); Axel Witsel (Atletico Madrid), Kevin De Bruyne (Manchester City), Youri Tielemans (Leicester City), Eden Hazard (Real Madrid), Yannick Carrasco (Atletico Madrid), Thorgan Hazard (Borussia Dortmund), Leandro Trossard (Brighton and Hove Albion), Amadou Onana (Everton), Leander Dendoncker (Aston Villa), Hans Vanaken (Club Brugge), Alexis Saelemaekeers (AC Milan); Dries Mertens (Galatasaray), Michy Batshuayi (Fenerbahce), Charles De Ketelaere (AC Milan), Dodi Lukebakio (Hertha Berlin), Lois Openda (Lens).