LONDON (Reuters) - Regulators should tailor their new liquidity reporting requirements for banks through better coordination among supervisors to cut costs, top banking associations said on Tuesday.

The Basel Committee on Banking Supervision is detailing global rules that will require banks to hold more cash or cash like instruments so they can withstand difficulties for at least a month without having to find fresh capital.

A failure to hold enough liquidity was seen as one of the key problems faced by banks at the height of the credit crunch, forcing governments to step in with taxpayer cash.

Banks would have to report regularly to supervisors about their liquidity levels but want to keep red tape costs to a minimum.

The International Banking Federation (IBFed) said the Basel Committee, which is made up of central bankers and regulators from nearly 30 countries, should use colleges of supervisors to help tailor reporting requirements for each bank.

A "one size fits all" approach to liquidity reporting was not the best way to ensure banks manage risk properly, IBFed said in a statement.

"This is particularly important for banks operating across international borders which are currently required to complete different reports for the authorities in different countries in which they operate," said Simon Hills, chair of IBFed's Basel working party.

The G20 group of leading countries, which are members of the Basel Committee, agreed last year to set up colleges for each major bank comprising all the main national regulators which supervise it in a bid to spot any problems earlier.