Meanwhile, Ukraine's security service raided the offices of Russian state media in Kiev and detained one journalist, moves the chief editor of Russia's RT television suggested were linked to the bridge opening.
The bridge limits the passage of vessels via the Kerch Strait to Ukrainian ports in the Azov Sea. Some Russians are calling it "Putin's bridge", created to link Crimea into Russia's transport network.
"At last, thanks to your talent, this project, this miracle, has happened", Putin told the workers. This was written by the President of Ukraine Petro Poroshenko on his page in Facebook on Tuesday, may 15. "Particularly cynical is the fact that its discovery comes on the eve of the anniversary of the deportation of the Crimean Tatar people by the Stalinist regime", - wrote Poroshenko.
After Russia's annexation of Crimea in March 2014, the peninsula found itself between a rock and a hard place. But many in Russia saw the move as restoring Moscow's rule over a historically Russian region.
Built at a cost of 228 billion rubles ($3.7 billion), the new structure, connects the southern Krasnodar region with the Crimean city of Kerch, spanning a strait between the Black and Azov seas. A railway bridge is due to be completed by the end of 2019. "Many didn't believe these plans were possible", Kremlin spokesman Dmitry Peskov told reporters on a conference call on Tuesday ahead of the ceremony.
"This is an extremely important day from this point of view and in a practical sense and in symbolic terms".
The motorway section of the bridge has over 60 road signs and ten automatic systems monitoring compliance with traffic regulations. It was originally expected to open in December but was finished ahead of schedule.
Putin sits in a dump truck before driving it on the newly-opened bridge.
Russian President Vladmir Putin on May 15 officially unveiled a 19-kilometer-long road bridge linking the annexed Crimean Peninsula with Russian territories across the Kerch Strait.
"Let me remind you, on my behalf to the Arbitration Tribunal of the UN Convention on the law of the sea was filed on protecting the sovereign interests of Ukraine, in particular, in connection with the illegal construction of the bridge Kerch", - said Poroshenko. He was hit with sanctions by the United States for his proximity to Putin and by the European Union for being among those accused of undermining Ukraine's territorial integrity.