The agency said its latest video, posted on the NCUA's YouTube channel, would help credit unions understand how the proposal differs from the FDIC's rule and Basel III.

“NCUA's risk-based capital proposal is complex, but its overall purpose is simple,” NCUA Board Chairman Debbie Matz said in a statement on Thursday. “This proposal has generated a great deal of discussion, and some misinformation, so we are providing the new video during the comment period to explain why a rule is necessary and how it would affect credit unions. We hope this will provide stakeholders with useful information as they evaluate the proposal.”

Both CUNA and NAFCU said the May 28 comment period should be extended by 90 days.

“Our organizations had previously asked for an extension of 90 days on Feb. 28, 2014, which was denied. We simply do not believe that the comment period provides sufficient time for a number of credit unions to analyze the proposal's impact on their individual operations and prepare their responses,” said the letter signed by NAFCU President/CEO Dan Berger and CUNA President/CEO Bill Cheney. “As the deadline for submitting comments is fast approaching, we again call for an extension of 90 days.”

The trade CEOs said the proposal is the most significant rule credit unions will likely face for years to come.

“Such an extension of the comment period will allow credit unions, which are struggling in a number of cases to meet new regulatory requirements this year, much needed additional time to provide the agency with substantive comments reflecting their particular situations,” they wrote.

“Given the health of the credit union system, we do not see the need to rush this rule and believe more time for comments will also benefit the agency through the production of well-reasoned letters,” the CEOs added.