Alex McLeish has named a 27-man group for the opening Euro 2020 qualifiers against Kazakhstan and San Marino.
McNulty has been rewarded for his scoring form since signing for Hibs in the January transfer window with his first ever call up. The on loan Reading striker has bagged six goals in six starts.
The 26-year-old joins Oli McBurnie, Oliver Burke and Johnny Russell as the forward options amid the absence of Leigh Griffiths, Steven Fletcher and Steven Naismith.
Souttar has been recalled at the first time of asking after spending nearly four months out of the game following a hip injury sustained in the Nations League defeat away to Israel.
The centre-back has been in strong form since returning for Hearts earlier this year.
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