OKSANA GRIGORIEVA is to receive an increase of $15,000 a month from ex-boyfriend Mel Gibson.

The Russian singer - who split from the actor amid claims he attacked her while the couple's 11-month-old daughter Lucia was in her arms - will now receive a total of $20,000 per month in child support payments from the 54-year-old star.

According to gossip website TMZ, Judge Scott Gordon - who is presiding over the couple's custody battle - issued an order yesterday (30.09.10) afternoon to raise Mel's maintenance payments.

However, Oksana is likely to be disappointed with the ruling, after reportedly requesting $60,000 a month from her former partner.

Last month, text messages were released in which the 40-year-old beauty claimed the 'Braveheart' star treats Lucia like an "illegitimate child".

She said: "U keep saying that ull take care of us in the most generous way. I wouldn't have played ur messages if u were keeping ur word. Even if u were just generous to Lucia, that would have been great. But u weren't. No where near the way u r generous with ur other children. U treated her as an illegitimate child. That's why I played the tapes. And my name wasn't mentioned at all. (sic)"