LONDON (Reuters) - European regulators could raise the bar on capital for banks like Deutsche Bank (>> Deutsche Bank AG) and BNP Paribas (>> BNP PARIBAS) in response to tough U.S. proposals to make banks less risky, potentially depressing profitability, Barclays analysts said.

The U.S. Federal Reserve has proposed that eight big U.S. banks should hold an extra capital cushion, which could require many to hold core capital of 12 percent of risk-weighted assets, significantly above the global minimum.

In Europe, regulators in Nordic countries, Switzerland and Britain have already set higher capital requirements than the global standard, but the bar is lower in most euro zone countries.

"The U.S. move to higher requirements ... begs the question whether Eurozone requirements also now move higher," Jeremy Sigee, analyst at Barclays, said.

Barclays analysts said Deutsche Bank, BNP Paribas and Societe Generale (>> SOCIETE GENERALE) would be most affected, and could need 15-20 percent more capital if they had to move to a 12 percent minimum standard.

That would depress their return on tangible equity, a measure of profitability, by between 1.6 and 1.9 percentage points each, Sigee said in a note on Wednesday.

Deutsche Bank's return on equity was less that 3 percent in the first nine months of the year, below the 12 percent it aims for in 2016 and a long way from its pre-crisis 20 percent.

It could also force banks to restrain dividends. Some, particularly French banks, could revise business plans and scale back activities, he said.

The changes would have little impact on Europe's other major banks, UBS (>> UBS Group AG), Credit Suisse (>> Credit Suisse Group AG) and HSBC (>> HSBC Holdings plc), as they are already planning for higher capital standards. Sigee said for them the U.S. move could mark a welcome levelling of the playing field.

The analysts do not cover Barclays Plc (>> Barclays PLC).

But Sigee and other analysts said it was too early to predict how the U.S. rules will play out.

Omar Fall, analyst at Jefferies, said most banks were already working towards higher capital levels than the minimum, with market pressure on banks to hold core capital of 11-12 percent.

The Fed wants U.S. banks whose failure could threaten markets to fund themselves more through shareholder equity and less by borrowing. Its proposals would take effect in 2016.

JPMorgan (>> JPMorgan Chase & Co.) could need $20 billion of extra capital. It said it will not keep as much excess capital over required levels as it might have and will make "surgical" changes to its business model.

(Reporting by Steve Slater. Editing by Jane Merriman)