"Have come to know through media about Mrs Sonia Gandhi's surgery. I pray for her speedy recovery and good health," the BJP leader wrote on Twitter.
Modi and Gandhi were engaged in a blatant war of words during various elections in Gujarat, where the Congress president had accused the Gujarat Chief Minister of being a "Maut ka Saudagur" (merchant of death). Modi had raked up the issue of Gandhi's foreign origin.
Making a bare announcement, Congress General Secretary Janardhan Dwivedi, told reporters in Parliament House today that the 64-year-old Gandhi was recently diagnosed with a medical condition and has been advised surgery.
"On the advise of her doctors, she has travelled abroad and she is likely to be away for two-three weeks," he said.