Hammers duo Jack Collison and Emmanuel Pogatetz could face each other on international duty next week with Wales due to take on Austria at Swansea City's Liberty Stadium on Wednesday.
Pogatetz, who arrived at the Boleyn Ground on loan from VfL Wolfsburg on Monday, has been capped 52 times by Austria and is in Marcel Koller's squad to take on Wales in their international friendly.
Collison, meanwhile, will be looking to add to his eleven Wales caps in that fixture - as well as getting one over his new team-mate.
West Ham will also have midfielder Mohamed Diame on international duty, as the 25-year-old has been named in Senegal's squad for their friendly against Guinea in Paris on Tuesday.
Goalkeeper Stephen Henderson completes the quartet of Hammers in senior international action next week as he is part of the Republic of Ireland squad for their home fixture against Poland on Wednesday.
In addition, winger Blair Turgott is in the England Under-19 squad, as Noel Blake's side begin their countdown to this summer's UEFA Under-19 Championships in Lithuania with a home match against Denmark in Doncaster on Tuesday.
Kieran Sadlier and January arrival Sean Maguire are in the Republic of Ireland Under-19 squad for a double header of home friendlies with the Czech Republic, on Tuesday and Thursday.
Meanwhile, Academy player Marcio Martins is in Portugal's Under-17 squad for the Algarve International Tournament, also involving England, Germany and the Netherlands, between 8-12 February.
Modibo Maiga's Africa Cup of Nations campaign goes on after he helped Mali to a penalty shootout victory over hosts South Africa in Saturday's quarter-final. The game ended 1-1 after extra time, but Mali held their nerve to progress and they will now go head-to-head with Ghana on Wednesday for a place in the final.
Jack Collison - Wales v Austria, Swansea, Wednesday 6 February
Emanuel Pogatetz - Wales v Austria, Swansea, Wednesday 6 February
Mohamed Diame - Senegal v Guinea, Paris, Tuesday 5 February
Stephen Henderson - Republic of Ireland v Poland, Dublin, Wednesday 6 February
Modibo Maiga - Mali - Africa Cup of Nations Semi-Final v Ghana, Durban, Wednesday 6 February
Blair Turgott - England U19 v Denmark U19, Doncaster, Tuesday 5 February
Kieran Saldlier & Sean Maguire - Republic of Ireland U19 v Czech Republic U19, Longford, Tuesday 5 February and Thursday 7 February
Marcio Martins - Portugal U17, Algarve Tournament, Friday 8 February - Tuesday 12 February