Opponents have locked in enough votes to block Senate ratification of the controversial Law of the Sea treaty championed by White House and the Pentagon.
The pact, which which would have created de facto rules for the world’s oceans, was heralded by Defense Secretary Leon Panetta and others as the key to maintaining peace and order in global hot spots such as the Asia-Pacific region.
On Monday, Sens. Johnny Isakson (R-Ga.), Rob Portman (R-Ohio) and Kelly Ayotte (R-N.H.) added their names to the growing list of anti-treaty advocates, who argue the pact does nothing to guarantee regional security along the waterways in the Pacific or elsewhere.
With their support, opponents now have the necessary three-fourths Senate majority to sink Senate ratification of the global maritime pact.
Isakson added his signature alongside 31 other Senate Republicans in letter against ratification of the global maritime deal sent to Senate Majority Leader Harry Reid (D-Nev.) earlier this year.
Portman and Ayotte issued a separate letter on Monday, voicing their intent to block Senate approval of the deal.