The U.S. trustee for bankrupt MF Global Holdings faces a wait to learn how much of the $700 million (445 million pounds) held by the failed broker's British subsidiary he can claw back on behalf of U.S. clients.

A source close to the process said on Wednesday it was too soon to talk numbers.

It is simply too early in the process to talk seriously about how much will be claimed back and it is largely dependent on how much is in segregated client funds and how much is from the general estate pot, the source said.

MF Global, like other brokers, separated large client accounts from each other and its own trading book, making these segregated accounts relatively easy to administer for trustees.

But smaller accounts did not enjoy this level of transparency and any claims by clients holding those accounts will be against the general cash pool to be shared out among all creditors.

MF Global UK administrator KPMG declined to comment on the U.S. claims.

The U.S. and British trustees are working behind the scenes to claw back MF Global client assets frozen when the trading firm collapsed on October31 and plan to start reimbursing clients as soon as possible.

KPMG said on Friday all but a tiny handful of the failed futures broker's British client positions had been closed or transferred and about 600 million pounds ($929 million) of client monies had been recovered.

The administrator plans a special meeting for clients and creditors on January 9 next year.

Investigators in the U.S. are searching for as much as $1.2 billion in missing customer money, which regulators believe may have been diverted out of client funds by MF Global for its own needs as it neared collapse.

Jill Sommers, who is heading the Commodity Futures Trading Commission's review of MF Global, said a week ago: We certainly don't want to lead anyone to believe we don't know what happened. We do know, and we see where all the transactions went.

(Editing by Jane Merriman)