Putin, at the wheel of a heavy KAMAZ truck, drove the full 19 km (12 miles) across the bridge from the Kerch Strait, which some Russians call "Putin's bridge" and which is created to link Crimea into Russia's transport network.
The Crimean Bridge, at 19 kilometres (nearly 12 miles) will be Europe's longest, overtaking Lisbon's Vasco da Gama Bridge.
Kyiv says the bridge is causing environmental damage and blocking passage for larger ships to ports on the Azov Sea, AFP reports.
"As one could predict, Washington is not happy", the Russian Embassy in the U.S. The four lanes of automobile traffic that open to the public on Wednesday will next year be joined by a railway, at a total cost of £2.7 billion. These and our other Crimea-related sanctions will remain in place until Russian Federation returns control of the peninsula to Ukraine. Some Russians are calling it "Putin's bridge", created to link Crimea into Russia's transport network. President Petro Poroshenko lambasted the bridge as "yet another piece of evidence of the Kremlin ignoring worldwide law" and "an attempt to legitimise the temporary occupation of the Crimean peninsula".
A parallel bridge for rail transport should be ready by December 2019, the Russian authorities stressed.
The Crimean Bridge at 19 kilometres will be Europe's longest overtaking Lisbon's Vasco da Gama Bridge Credit Screengrab from RT
Crimea was annexed from Ukraine following the 2014 Ukrainian revolution and takeover of the area by pro-Russian separatists and armed forces.
"Putin initiated this project himself. Many didn't believe these plans were possible", Kremlin spokesman Dmitry Peskov told reporters.
Putin annexed Crimea, a Ukrainian peninsula in the Black Sea, in 2014, after claiming that ethnic Russians in the region were threatened by Ukraine's pro-Western revolution.
British Foreign Office minister Alan Duncan said it was "a further example of Russia's reckless behaviour".
In a symbolic gesture meant to wow the millions of his followers, the Russian president climbed aboard an orange Kamaz truck and, with other similar trucks of various colors trailing behind, started to roll down the brand new tarmac.
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