Nine divisions of U.S., British, German and Polish troops could be called on to defend the Baltic states and Poland in the event of an attack from Russia, according to a secret NATO defense alliance contingency plan revealed by the WikiLeaks organization.

The plan, reported on Dec. 6 by the Guardian newspaper in London, would include Latvia, Estonia and Lithuania along with Poland in a regional defense strategy called “Eagle Guardian,” according to one diplomatic cable. Its approval was urged by Germany.

The document is one of about 250,000 U.S. diplomatic cables the WikiLeaks organization says it has acquired and is releasing on its website and through several newspapers.

U.S. Secretary of State Hillary Rodham Clinton in January signed off on the NATO plan, according to the cables, the Guardian reported. The plan is part of an effort to refocus NATO’s defense strategy.

Latvia in 2004 joined NATO along with Bulgaria, Estonia, Lithuania, Romania, Slovakia and Slovenia. Under Article 5 of the NATO defense treaty—originally approved in 1949—all members of the alliance agree to defend each other in the event of an armed attack. However, the Guardian noted, “the three Baltic states have complained they are treated as second-class members because their pleas for detailed defence planning under NATO’s ‘all for one and one for all’ article 5 have been being ignored.”

Although economic relations between the Baltics and Russia have improved, political tensions remain. Russia has frequently alleged Latvia and Estonia discriminate against their large Russian-speaking minorities.  In 2007, the Guardian story reminded readers, a cyber-attack against Estonia was suspected to have originated in Russia. Last year, Russia staged military exercises that simulated an invasion of the Baltics and a nuclear attack on Poland, the newspaper reported.

The contingency plan pleased Latvia, according to a December 2009 cable from the U.S. Embassy in Rīga posted on the Guardian website.

Kaspars Ozoliņš, director of security policy in the Ministry of Foreign Affairs, “expressed his government’s profound happiness” at the plan, according to the cable.

The contingency plan apparently also was discussed during last month’s NATO summit in Lisbon, Portugal.

NATO leaders adopted a new and broad Strategic Concept during the summit. The document is meant to serve as a roadmap for the alliance over the next 10 years. It reaffirms NATO’s principle of mutual defense, but also opens the door to increased cooperation with Russia.

“NATO-Russia cooperation is of strategic importance as it contributes to creating a common space of peace, stability and security,” according to the Strategic Concept. “NATO poses no threat to Russia. On the contrary: we want to see a true strategic partnership between NATO and Russia, and we will act accordingly, with the expectation of reciprocity from Russia.”

Latvia leaders—including President Valdis Zatlers, Defense Minister Artis Pabriks and Foreign Minister Ģirts Valdis Kristovskis, all of whom attended the Lisbon summit—endorsed the Strategic Concept, saying the document strengthens the country’s defense.

Zatlers is scheduled to visit Russia from Dec. 19-21.