Amid uncertainty over leadership issue in the Congress , senior party leader AK Antony on Friday said Sonia Gandhi is its leader and will remain continue till the time the party wants."Don't worry about Rahul Gandhi also, he will come back with more strength," he told reporters at a press conference.Responding to a query on whether Sonia Gandhi should take responsibility and step down after Congress' defeat in the assembly polls, Antony told the reporters who asked the question not to be "unduly concerned" about the Congress and bother about their writings instead."Sonia ji is our supreme leader. She is a Congress person and she will continue to lead the Congress to success as long as the party wishes... she made the sacrifices because of the unanimous request of the entire Congress party. Don't be concerned about Sonia Gandhi ji's issue, she is our president, she will continue as long as she and the party want," Antony said.The Congress has grappled with leadership for a few months now ever since the party lost the Lok Sabha election and Rahul Gandhi resigned as party chief.