Big banks will have to set aside more profits or even raise capital as protection against hard times from 2012 under tough new proposals from international regulators, released on Thursday.

The new rules from the Basel Committee on Banking Supervision will introduce higher standards for the core assets banks have to hold and stricter requirements on liquidity holdings.

The fully calibrated set of standards will be developed by the end of 2010 to be phased in as financial conditions improve and the economic recovery is assured, with the aim of implementation by end-2012, the committee said in a statement.

The new rules include measures to encourage the build-up of capital buffers in good times that can be drawn down in bad times and a global minimum liquidity standards for internationally active banks.

(Reporting by Sven Egenter, writing by Krista Hughes)