(Adds comments from bank experts in paragraphs 9-18)

"Such statements are more of a faux pas by Frenkel's lawyers than a clever PR move," Yurgens said.

Pavel Medvedev, deputy chairman of the Duma's banking committee, said Frenkel's letter offered no evidence.

"It is an unsubstantiated statement that offers no proof," he said, adding that Frenkel had addressed him six months ago asking him to amend banking legislation.

"He wanted [financial] monitoring laws to be fully formalized, but I explained to him that was impossible," Medvedev said.

Financial control, the parliamentarian said, is not only an assessment of formal figures reported by banks, but also includes the professional judgments of auditors, and that cannot be formalized, he said.