Ukrainians are celebrating the first day of visa-free travel to most EU countries, which President Petro Poroshenko welcomed as a "a final exit of our country from the Russian Empire," RFE/RL reports.

The liberalized regime entered into force on June 11, allowing Ukrainian citizens who have biometric passports to enter all EU member states other than Ireland and the United Kingdom without a visa for up to 90 days during any 180-day period. It also applies to four Schengen Area countries that are not in the EU: Norway, Iceland, Liechtenstein, and Switzerland.

Poroshenko met with his Slovak counterpart, Andrej Kiska, on the Slovak-Ukrainian border, opening a symbolic "door to the EU."

"We have waited so long for this," the Ukrainian president said at the Uzhhorod border crossing in the Zakarpattia region. "I am sure that this day, June 11, will go down in the history of Ukraine as a final exit of our country from the Russian empire and its return to the family of European nations. "Welcome to Europe," Kiska told the crowd attending the event. "I want to call on you to continue carrying out reforms."

"The visa-free regime for Ukraine has started! Glory to Europe! Glory to Ukraine!" Poroshenko earlier wrote on Twitter after hundreds of Ukrainians crossed the EU border.

"Flights to Warsaw, Budapest, Frankfurt, and Munich have successfully landed and passed passport control;) #Bezviz -- just the beginning!" Foreign Minister Pavlo Klimkin cheered on Twitter.

Thousands of people had crossed the border into EU countries by midday, the Ukrainian Foreign Ministry's consular department wrote on Twitter.

Ukrainian travelers arriving in Brussels on June 11 said they were pleased about the ease with which they could now travel to Europe and the greater integration with the EU that it represented.