"I think not all of them should be charged, but Smith should be charged," Gonzalez said, referring to the principal accused, Corporal Daniel Smith.

Smith faces charges of raping a 22-year-old Filipina in the former US naval base of Subic following US-Philippine military exercises in October.

Accused of conspiring with Smith in the alleged crime are Marine Sergeant Chad Carpentier and corporals Keith Silkwood and Dominic Duplantis.

Gonzalez said the Justice Department would early this week issue a resolution on Smith's appeal to have the rape charge dropped.

The resolution is expected before Smith and his co-accused are arraigned on March 24 at a court near Subic, when they will be given a chance to face their accuser and enter a plea of guilty or not guilty.

The local court does not have to heed the Justice Department's resolution but it will have strong influence in deciding who will be charged.

The Marines have insisted only one of them had sex with the woman and that the act was consensual.

Lawyers for Smith and Carpentier have confirmed their appearance for the arraignment while a lawyer for Silkwood and Duplantis has said he is still studying whether to bring his clients to court.

The men are in the custody of the US embassy. It has refused to hand them over to local authorities, citing a provision in a "visiting forces agreement" that allows them to keep soldiers in their custody during legal proceedings.