Defoe has been a lethal finisher for relegation-threatened Sunderland, scoring 14 of the club's 24 league goals this season but has not played for England since he won his 55th cap in November 2013.
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Gareth Southgate's squad has been depleted by the absence of striker Harry Kane, who damaged ligaments in Tottenham Hotspur's 6-0 FA Cup quarter-final win over Millwall last weekend, and Manchester United's Wayne Rooney.
Defoe is the top English scorer in the Premier League after Kane, who has 19 goals to his credit.
England play Germany in Dortmund next Wednesday and Lithuania at Wembley on March 26.
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