Manila - The Philippine Supreme Court on Wednesday ruled that an American soldier convicted of rape in 2006 should be detained in a local facility instead of the US embassy, where he has been staying since his conviction.

The high tribunal, voting 9-4, ordered the Department of Foreign Affairs to negotiate for the transfer of US Marine Lance Corporal Daniel Smith, 23, to a detention facility that is under the control of Philippine authorities.

Smith was convicted on December 4, 2006, of raping a Filipino woman in Olongapo City, 90 kilometres north of Manila, the year before. He was sentenced to 40 years in prison.

Sith has appealed his conviction, and the US embassy insisted that a visiting forces agreement (VFA) between the Philippines and the United States allows for Smith to remain in US custody until the conviction becomes final.

The VFA details the rules on the treatment of US forces visiting the Philippines for training and joint military exercises with Filipino troops.

But the Supreme Court ruled that the agreement between Philippine Foreign Secretary Alberto Romulo and US Ambassador Kristie Kenney to detain Smith at the US embassy was not in line with the VFA, according to tribunal spokesman Midas Marquez.

"While the VFA is constitutional, the Romulo-Kenney agreement which provided for the transfer ... to the embassy is not in accordance with the VFA," he said.

Marquez added that the high tribunal ordered Romulo to "negotiate with the US representatives for the appropriate agreement on detention facilities under Philippine authorities."

The court did not indicate a timeline for the negotiations in its ruling, but Marquez said it wants the talks to take place immediately.

Smith's transfer to the US Embassy from the Makati City jail in metropolitan Manila just weeks after his conviction triggered public outrage in the Philippines, with critics accusing the government of succumbing to pressure from the US.

Smith was one of thousands of US soldiers who participated in joint military exercises in the Philippines in 2005. His co-accused - Lance Corporals Keith Silkwood and Dominic Duplantis and Staff Sergeant Chad Carpentier - were acquitted for lack of evidence. (dpa)