Mr Dikshit, a former party MP, was part of the G-23 leaders.
Congress leader Sandeep Dikshit on Friday expressed dismay and a "sense of betrayal" over Ghulam Nabi Azad's resignation from the party, and said quitting strengthens the policies, systems, and people that made them write the "letter of reform" in the first place.
Mr Dikshit, a former party MP, was part of the G-23 leaders who had written to Congress chief Sonia Gandhi in August 2020 for an organisational overhaul and reforms, saying it was a "banner of reform and not a banner of revolt".
"When I read your letter of resignation, it gave me a sense of dismay and unfortunately, then a sense of betrayal," he wrote to Mr Azad.
His letter came soon after senior Congress leader Ghulam Nabi Azad resigned from all party positions, including its primary membership, ahead of organisational elections and accused the leadership of committing "fraud" on the party in the name of "sham" internal polls.
In his letter, Sandeep Dikshit, son of former Delhi chief minister Sheila Dikshit, told Mr Azad that he has known him in his capacity as a citizen of India, Congress sympathiser, Congress worker, and then as Congress MP and that he had great respect for his work and ability.
"I wholeheartedly and in full agreement signed the letter that you had written to the Congress president, and became a part of what some media people called the G-23.
"The matter we raised in that letter, and the spirit in which many of us signed it and many others supported what was written in it, was in many ways a pathway to revitalise this greatest of political parties, that lies, as you say in your letter also, in its darkest abyss today. But to my mind, we, and I in it, had raised the banner of reform, not a banner of revolt," the former Delhi MP said.
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