The European Union signed Friday agreements for deeper political and economic integration with Ukraine, Georgia and Moldova.

Leaders of the three ex-Soviet states attended a ceremony in Brussels which marked the step strengthening ties with Europe despite previous Russian resistance.

"Perhaps [this is] the greatest day for our country after independence in 1991," UNIAN news agency quoted Ukrainian President Petro Poroshenko as saying.

Moldovan and Georgian Prime Ministers, Iurie Leanca and Irakli Garibashvili, also took part in what establishes a free trade zone with the 28-nation bloc.

In Ukraine, plans of former President Viktor Yanukovych to abandon the signing of a deal with the EU in favour of a closer union with Russia infuriated thousands and led to mass protests which later triggered a wave of violence in the streets of Kiev and other cities and left tens of people dead.

After Ukraine's Parliament ousted Yanukovych, the Kiev interim leadership vowed Ukraine was to take a path toward EU integration.

Association Agreements are thought to be a suitable EU instrument in relations with states that are not immediate member candidates.

EU Commission President Barroso described the new Association Agreements as "a recognition for the significant progress" observed in the three states over the last years.

European Council President Herman van Rompuy promised that EU visas are to be scrapped for Georgia and Ukraine (the union has already made the move for Moldova).

He added "full integration" of the three economies into the EU market was "a common goal" which would "push societies closer" and "ensure a better and more secure life".

Russia confirmed the three states' right to strike agreements with the EU, but warned it would act if their actions affect its own economy.

"Russia is to take measures in case the consequences of these agreements bring harm to its market," President Vladimir Putin's press secretary Dmitry Peskov was quoted by ITAR-TASS as saying.

Peskov explained the set of protective measures was "evident", but stopped short of elaborating.

President Putin himself argued the Kiev leadership and its "anti-constitutional coup" earlier this year forced Ukrainian people to make an "artificial choice between Russia and Europe".

Russia already has free trade agreements with Moldova and Ukraine and maintains good commercial relations with Georgia through a number of documents.