Both players are to be confirmed as new additions to the squad, according to the Edinburgh Evening News, and will join up with the national team on Monday ahead of this week’s meeting with Poland at Hampden Park.
Injuries to John Souttar, Liam Cooper and Scott McKenna left Clarke short of defensive options and he has turned to Halket t having watched the 26-year-old several times in recent months with the centre-back’s displays a major contributing factor to Hearts’ 14-point lead in third place in the Scottish Premiership.
Stewart is also expected to be included after 22 goals in 43 games for Sunderland this season with Queens Park Rangers forward Lyndon Dykes named in the squad but still recovering from injury.
Stewart, 25, left Ross County to join Sunderland in January 2021 for an undisclosed fee and quickly developed into a key player for the English League One club. His goal threat will now be tested at the top level in amongst international regulars.
Scotland play Poland on Thursday before a second friendly next Tuesday. That will be away against the losers of the Wales-Austria World Cup play-off semi-final after FIFA and UEFA chose to rearrange this week’s fixtures.
The war in Ukraine forced the postponement of Scotland’s play-off tie against the Eastern Europeans, which has been rescheduled for June in the hope that peace can break out.