Updated

Two former senators, lawyers and activists asked the Philippine Supreme Court on Monday to rule on the constitutionality of an agreement with the United States that gives the American military greater access to bases across the country. They also urged the court to halt the pact's implementation until it issues a ruling.

The Enhanced Defense Cooperation Agreement signed hours before a visit last month by President Barack Obama will allow thousands of U.S. troops to be temporarily based in Philippines for the first time in more than 20 years, signaling closer cooperation in the allies' hot-and-cold relationship that has been shaped over the decades by war, terrorism and now, jitters over China's growing military might and assertiveness.

Former Senators Rene Saguisag and Wigberto Tanada — two of 12 senators who voted to kick the U.S. military bases out of the Philippines in 1991 — and 10 taxpayers filed the petition, suing five officials including President Benigno Aquino III's defense, foreign affairs, budget and executive secretaries and the armed forces chief of staff for abuse of discretion.

The petition says the 10-year agreement violates the constitutional ban against the presence of foreign military bases or troops in the country except under a treaty approved by two-thirds of all Senate members. The constitution also says if Congress requires, the agreement should be ratified by majority of Filipinos in a referendum, and recognized as a treaty by the other contracting state.

"Not only is the EDCA a violation of the Philippine Constitution, it also does not provide any substantial, long-term real benefit, much less distinct advantage or improvement in our position vis-à-vis the United States," the petition said.

It said the agreement was wrongly framed as a furtherance of the 1951 Mutual Defense Treaty and the 1998 Visiting Forces Agreement and so evading the constitutional requirement for concurrence of the Senate.

But the petition said the 1951 treaty was superseded by the 1987 Constitution and "its express renunciation of war as an instrument of national policy." And the presence of U.S. troops under the new agreement goes beyond "visiting," ruling out the 1998 agreement as an anchor, the petition said.