New York has banned a unit of PriceWaterhouseCoopers from accepting certain consulting work from New York-regulated firms for two years after charging the "Big 4" accounting firm with removing a warning about financial information from countries facing U.S. sanctions.

The state's Department of Financial Services says the firm's Regulatory Advisory Services Group caved to pressure from Bank of Tokyo-Mitsubishi to strip wire transfers of information that would have triggered sanctions compliance alerts.

In June 2013 BTM paid a $250 million fine for violating U.S. sanctions.

"When bank executives pressure a consultant to whitewash a supposedly 'objective' report to regulators — and the consultant goes along with it — that can strike at the very heart of our system of prudential oversight,” DFS Superintendent Ben Lawsky said in a statement.

DFS accuses PwC of having first acknowledged that data manipulation would comprise the integrity of an ongoing "historical transaction review," but then deleting the information anyway.

"At the Bank’s request, PwC ultimately removed the original warning language from the final HTR Report the Bank submitted to regulators and, in fact, inserted a passage stating the exact opposite conclusion: '[W]e have concluded that the written instructions would not have impacted the completeness of the data available for the HTR and our methodology to process and search the HTR data was appropriate,'” DFS says.

One PwC director, now retired, warned against doing a more thorough review of the wires because doing so would "open up a whole other can of worms,” DFS says.

PwC has also agreed to pay a $25 million fine. Here's the full consent agreement:

PwC Full Agreement