MOSCOW, June 17 (Reuters) - President Vladimir Putin said on Friday that his deployment of tactical nuclear weapons to Belarus, something he confirmed for the first time had already happened, was a reminder to the West that it could not inflict a strategic defeat on Russia.

Speaking at Russia's flagship economic forum in St Petersburg, Putin said Russian tactical nuclear warheads had already been delivered to close ally Belarus, but stressed he saw no need for Russia to resort to nuclear weapons for now.

"As you know we were negotiating with our ally, (Belarusian President (Alexander) Lukashenko, that we would move a part of these tactical nuclear weapons to the territory of Belarus - this has happened," said Putin.

"The first nuclear warheads were delivered to the territory of Belarus. But only the first ones, the first part. But we will do this job completely by the end of the summer or by the end of the year."

The move, Moscow's first deployment of such warheads - shorter-range nuclear weapons that could potentially be used on the battlefield - outside Russia since the fall of the Soviet Union was intended as a warning to the West about arming and supporting Ukraine, the Russian leader said.