MOSCOW - Russian President Vladimir Putin said Thursday that Russia faces unfair criticism and needless military threats from the West, lashing out in an annual news conference at U.S. plans for missile defence sites in former Soviet satellite states and at suspicions that Moscow is wielding its energy wealth for political purposes.

Putin held forth on a broad range of issues at the more than 3�-hour marathon, but he left two key questions unanswered: whom he wants to succeed him and who he believes is behind the shocking slayings of Kremlin critics that have damaged his reputation and will cloud his legacy after he steps down.

Putin presented a wide overview of Russia seven years after he was handed its helm: economically robust but plagued by an income divide, uneasy about the intentions of the United States in Europe and insistent on its reliability as a major energy supplier.

Russia's relations with the West are a perennial topic at the news conference, which gives foreign journalists a rare chance to directly ask Putin a question, and gives Putin a chance to portray Russia, as he often does, as a country under attack from ill-wishers abroad.

He spoke harshly against the possible deployment of elements of an American missile defence system in Poland and the Czech Republic, scoffing at U.S. claims that they would be aimed at intercepting possible missile attacks from Iran and saying Russia would take unspecified retaliatory measures.

"We consider such claims unfounded, and, naturally, that directly concerns us and will cause a relevant reaction,'' he said, suggesting Russia will continue to develop weapons that would iron out what Russian military officials have said would be a strategic imbalance.

He said that while missile defence systems under development will only be capable of tackling ballistic missiles, Russia is developing new weapons that will be capable of changing the altitude and direction of their flight on their way to target.

"Missile defence systems are helpless against that,'' Putin said.

In the wake of energy price disputes with Belarus that interrupted Russian oil supplies to Europe this winter and deepened western concerns about Russia's reliability as an energy supplier, Putin rejected suggestions that the country is using energy as a political weapon.

"The thesis is being thrust on us all the time that Russia is using its old and new economic efforts to attain foreign policy goals. It is not so,'' Putin said, adding that journalists who advanced such ideas were "ill-wishers.''

Also seeking to harm Russia, he said, are "oligarchs who have fled'' Russia to avoid prosecution and live in western Europe or the Middle East, clear references to bitter Kremlin critics including Boris Berezovsky in Britain and Leonid Nevzlin in Israel.

Putin, however, stopped short of suggesting, as Russian prosecutors, pro-Kremlin legislators and state-run media have done, that Berezovsky or Nevzlin could have been behind the fatal poisoning of former security agent Alexander Litvinenko.

He stressed that only investigators and courts could determine who was behind the killings last year of Litvinenko and investigative journalist Anna Politkovskaya, and suggested he did not subscribe to theories linking the slayings.

"I don't very much believe in the conspiracy theory, and honestly speaking, it doesn't bother me very much,'' Putin said.

The Kremlin has denied Litvinenko's deathbed accusation that Putin was behind his slaying, and Putin reiterated his assertion that Russian authorities would have no reason to kill him, portraying him as a small fry who had no access to secrets during his service.

The cool words toward the West were peppered amid questions that focused mainly on domestic matters. Always one of Russia's main media events, this year's news conference set new records for its length of three hours, 32 minutes, which is six minutes longer than last year, and the number of journalists accredited: 1,232.

Putin fielded an array of queries on issues spanning the spectrum from Iran's nuclear program to water levels in a Russian reservoir to what he does to brighten up a bad mood. Answering the last question, he said he talks to his dog, Connie, who "gives good advice'' or reads Omar Khayyam poems from a book his wife, Lyudmila, gave him. "I recommend it,'' Putin said.

Those personal details, along with touches like a flirtatious exchange with a young reporter from Murmansk and a joke about Soviet-era drinking habits, are part of his annual effort to portray himself as a regular guy on top of being a competent, caring president in control of a resurgent country with a growing economy and global clout.

Putin hailed Russia's economic growth but added that maintaining the pace and bridging the yawning gap between rich and poor will be a key task for his successor and for the government after his term is up.

Despite being pestered repeatedly, he refused to say who that might be.