Moscow ? Russia said Saturday it will suspend participation in a key European arms control treaty, halting NATO inspections of its military sites and no longer limiting the numbers of its tanks and other heavy conventional weapons.

The move, threatened for months, added new tension to relations with the West already strained over U.S. plans to build a missile shield in Eastern Europe, Russian conflicts with its neighbors and Western criticism of Moscow’s human rights record.

The suspension is to take place 150 days after Russia officially notifies all the countries concerned of its intention.

Experts said the move was a symbolic gesture rather than a sign of Russian intent to build up forces near its borders. The Kremlin, they said, appeared to be expressing its dissatisfaction with the perceived U.S. domination of global affairs, and positioning Russia as an unyielding global player.

The Conventional Forces in Europe Treaty was signed by Russian and NATO members in 1990, when Soviet and NATO troops faced off in Central Europe. It was amended in 1999 to reflect changes since the breakup of the Soviet Union, adding the requirement that Moscow withdraw its forces from the former Soviet republics of Moldova and Georgia.

Russia has ratified the amended version and slowly moved to withdraw its forces in recent years. The United States and other NATO members have refused to commit to the revised treaty until the withdrawal is complete.