Story highlights Bernie Sanders has repeatedly called on the Clinton campaign to release her speeches

"What his agenda is is the future of the Democratic Party," Jane Sanders said

Washington (CNN) Bernie and Jane Sanders won't release their back tax returns until Democratic rival Hillary Clinton releases the transcripts of her Wall Street speeches, Jane Sanders said Tuesday afternoon.

Bernie Sanders has repeatedly called on the Clinton campaign to release her speeches in an effort to show she's aligned with powerful Wall Street interests.

But he has been slow to answer Clinton's demand to release his tax returns, saying in a CNN debate earlier this month that his wife handles their financial affairs and has been too busy campaigning. The Sanders made public their 2014 return the next evening, showing they earned nearly $206,000 and paid about $28,000 in federal taxes that year.

Asked Tuesday when the campaign plans to issue prior years' returns, Jane Sanders told CNN's Wolf Blitzer they will wait to see whether Clinton will disclose her transcripts.

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