Sri Lanka Cricket said in a statement on Monday that 36-year-old Jayawardene, who has played 407 ODIs and scored over 11,000 runs, had requested leave on personal grounds.
Left-handed batsman Kithuruwan Vithanage, who has played two tests but has yet to represent Sri Lanka in limited overs cricket, was named as his replacement.
Left-arm spinner Rangana Herath was named in the one-day squad but was not considered for the Twenty20 series as "he was being rested considering the excessive amount of cricket he played and the available cricket for him up to the 2015 World Cup."
Sri Lanka play Pakistan in two T20 internationals in Dubai on December 11 and 13 before moving to Sharjah for the start of the five-match one-day international series on December 18.
Image: Mahela Jayawardene
Photograph: Reuters
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