NEW YORK, April 23 (Reuters) - Moody's Investors Service on Wednesday cut its ratings on GMAC LLC and its residential mortgage unit ResCap LLC deeper into junk territory, and said it may cut them both again on ongoing losses from residential mortgage loans and capital concerns.

The downgrade of ResCap is due to the resignation of the two independent directors on the mortgage lender's board, who had been responsible for looking after the interests of ResCap's creditors, Moody's said.

"The absence of independent directors increases the likelihood that ResCap will take actions that are negative for creditors," Moody's analyst Craig Emrick said in a statement.

Under terms of ResCap's operating agreement with GMAC, however, the lender cannot file for bankruptcy unless its board has at least one independent director and a majority of the independent directors approve the action, Moody's said.

Moody's cut ResCap's credit rating two notches to "Caa1," seven steps below investment grade, from "B2."

The review for further downgrade will focus on ResCap's ability to fund itself after its $1.75 billion bank loan matures in July 2008. It also has an undrawn $875 million credit line maturing in June 2008.

Moody's also cut GMAC's rating one notch to "B2," five levels below investment grade, from "B1," saying it will likely need to financially support its ailing mortgage unit.

GMAC in February posted a $724 million fourth-quarter loss, pulled down by a $921 million loss at ResCap, which recorded its fifth straight quarterly loss. For details, see [ID:nN05553735]

"Further operating weakness at ResCap poses risks to GMAC's capital position and liquidity that exceed previous estimates," Moody's said.