Washington ? The Senate unanimously endorsed the addition of seven former communist nations to NATO on Thursday in what would be the largest expansion of the alliance formed as a bulwark against Soviet military power.

With the vote, the United States becomes the third NATO member to have approved the expansion, joining Canada and Norway. Senators said the new members would boost the alliance, strengthen American security and encourage democracy throughout Europe.

The 16 remaining NATO members must also endorse the expansion for Bulgaria, Estonia, Latvia, Lithuania, Romania, Slovakia and Slovenia to be admitted to the alliance.

President Bush hailed the expansion in a White House ceremony attended by the expansion nations’ foreign ministers, who had looked on from the Senate gallery during the earlier vote.

Noting that Thursday was the 58th anniversary of the allied victory over Germany in World War II, Bush said, “Today on V-E day, we mark another kind of victory in Europe.”

“These heroic nations have survived tyranny, they have won their liberty and earned their place among free nations,” Bush said. “America has always considered them friends and we will always be proud to call them allies.”

The president also took the opportunity to press for NATO to develop new military capabilities “to confront the emerging dangers of a new era” — primarily terrorism.

Secretary of State Colin Powell, center, joins hands with foreign ministers from the newest members of NATO at the State Department in Washington. From left are, Slovakian Foreign Minister Eduard Kukan, Powell, and Lithuanian Foreign Minister Antanas Valionis. The Senate endorsed adding seven former Soviet bloc countries to NATO in what would be the largest expansion of the alliance since it was formed as a bulwark against Russian military power.

The Senate’s unanimous vote came despite doubts by many lawmakers about the future of the alliance, following a rift over the Iraq war.

“This is historic for these seven countries, vital in continuing to strengthen the North Atlantic alliance and central to U.S. security and relationships in the world,” said Foreign Relations Committee Chairman Richard Lugar, R-Ind.

The 96-0 vote contrasted with the heated debate that surrounded the last round of expansion five years ago, when the Senate voted 80-19 to add the Czech Republic, Hungary and Poland.

A two-thirds vote is needed for treaty ratification.