The European Union must reset its ties with Russia, Hungarian Prime Minister Viktor Orban said Friday, fresh from agreeing a major nuclear deal with Moscow.

"The EU has to rebuild its ties with Russia in a pragmatic manner, because the EU needs energy for its sustainable economic development," the right-wing Orban told a conference of central bankers in Budapest.

"As you know I am an old anti-communist, but if Europe fails to do its utmost to secure Russian energy, I am not sure how it is going to supply its economy," said Orban, 50, who is running for re-election in EU member Hungary on April 6.

Orban, who as a youth activist made a famous speech in 1989 before the fall of communism that year and who has warned against too much influence from Moscow since, this month signed a big nuclear deal with Russian President Vladimir Putin.

Under the accord, agreed without a formal bidding process, Moscow will build two new nuclear reactors at Hungary's sole atomic power plant at Paks -- and will loan Hungary up to 10 billion euros ($13.7 billion) to pay for it.

Putin has long been accused of using the dependence of former communist countries in eastern Europe on Russian oil and gas as a political tool -- not least in Ukraine, currently in major political turmoil -- which has frayed ties with Brussels.

Orban also said that nuclear power was key to solving Europe's energy problems.

"Europe will never succeed if it cannot supply energy at a competitive price, and to do that, the role of nuclear energy needs to be reconsidered," he said.