Spain vetoed the EU's participation in the Operation Prosperity Guardian despite the government's advocating for whole Europe to join the mission several hours before, the newspaper reported.
Spain has not explained the u-turn on the policy to the partners, the newspaper reported on Thursday.
On Monday, the US launched an international operation aimed at protecting commercial ships in the Red Sea from the attacks of Yemen's Ansar Allah rebel movement, also known as the Houthis. On Thursday, Pentagon spokesman Patrick Ryder said that more than 20 countries had so far signed on to participate in the coalition.
The Houthi rebels vowed they will continue to prevent the passage in the Red Sea and the Arabian Sea of ships linked to Israeli companies or bound for Israel until the latter's military actions in the Gaza Strip end.