"Sonia Gandhi is currently travelling on a short international visit for personal reasons," the party's chief spokesman Randeep Surjewala said.
Party sources said she and Priyanka had left together earlier, while Rahul Gandhi flew out today.
Though the reason for their travel was not clear, the talk in party circles is that Sonia Gandhi will be away for a week while Rahul is expected to be back next week.
Image: A file photograph of the Gandhi family.
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