Alasdair McDonnell says Conall McDevitt 'successor'
The SDLP leader Alasdair McDonnell has described Conall McDevitt, who quit politics this week, as having been a leader in waiting.
He also denied the pair had been at loggerheads.
He described the former South Belfast MLA as his closest friend and confidante in politics.
Mr McDevitt quit politics over a failure to declare more than £6,000 earned from a public relations company soon after he was appointed as an MLA.
Dr McDonnell broke his silence on the resignation after reporters waited for him outside his party headquarters.
He said Mr McDevitt would remain as a key adviser and described him as having a very high standard of ethics. On Thursday, Mr McDevitt said he would not be returning to public life in future.
Dr McDonnell called him a "very valued member of the assembly".
"He had made a tremendous impact, he was the runner-up in the leadership contest two years ago and certainly Conall was seen as my successor," he said.
"He certainly earned that and he continued to earn that reputation.
"But I think the point from us is that Conall has asked for privacy. We fully respect his privacy."
When he announced his resignation Mr McDevitt said that between March 2010 and August 2010 he had received a total of £6750 from his former employers, Weber Shandwick.
"I resigned as managing director of the Belfast office in December 2009 and I provided support and mentoring to the new management team following my departure from the company," he said.
"I was never asked to nor did I ever represent any of the company's clients whilst an MLA.
"These payments were made through JM Consulting, a consultancy which my wife has an interest in. These are registerable interests under the Assembly rules. I have now registered these earnings on my register."
Mr McDevitt said the earnings should have been declared but were not.
"That's a serious breach, in my opinion, of the code," he said.
"I have rectified it today, but I entered politics to try and bring about change and positive change, and I feel I have fallen below the standards expected of someone in public life.
"Therefore I think there's a duty on me to resign my position in public life in order to protect the integrity of the institution and to acknowledge the error that I have made, for which I am obviously deeply sorry."
Mr McDevitt had represented the South Belfast constituency at the Northern Ireland assembly since January 2010.