Russian President Dmitry Medvedev has slammed Prime Minister Vladimir Putin's criticial comments on military action against Libya as "unacceptable", in the most public clash yet between Russia's ruling tandem.
Putin earlier today denounced the UN resolution allowing military action on Libya as resembling a "medieval call to crusade", in one of his most virulent diatribes against the West in years.
"Under no circumstances is it acceptable to use expressions which essentially lead to a clash of civilizations. Such as 'crusade' and so on," Russian news agencies quoted Medvedev as saying.
"It is unacceptable. Otherwise, everything may end up much worse compared to what's going on now. Everyone should remember that."
Medvedev took over the Kremlin in 2008 after Putin served two four-year terms as president. Putin immediately became a powerful prime minister and until now the two men have steered clear of clashes in public.
"The resolution by the Security Council, of course, is defective and flawed," Putin told workers on a visit to a missile factory in the central Russian region of Udmurtia.
"To me, it resembles some sort of medieval call to crusade when someone would appeal to someone to go to a certain place and free something there," he said in televised remarks, referring to the expeditions by armies in the Middle Ages to end Muslim rule over the holy land.
The Russian premier also lashed out at the "steady trend" of US military intervention around the world, accusing Washington of acting without conscience.
"I am concerned about the ease with which the decision to use force was taken," Putin was quoted as saying in reference to the current international campaign in Libya.
Noting that the United States had already involved itself in the former Yugoslavia, Afghanistan and Iraq, Putin added: "Now it's Libya's turn.
"And all of this under the guise of protecting peaceful civilians. Where is the logic, where is the conscience? There is neither one nor the other," Putin said.
Putin added that the events in Libya showed that Russia had taken the right decision in strengthening its military capabilities, in possible reference to its massive new $650 billion rearmament plan.
"Today's events in Libya prove that we are doing everything right in terms of strengthening Russia's military capabilities," he said.
He also announced that Russia planned to double the production of strategic and tactical missile systems from 2013.
"Already from 2013 production of missile systems should virtually double," Russian news agencies quoted Putin as saying.
Russian air-defence troops would also receive the S-400, an advanced surface-to-air missile system, as part of a current army overhaul, Putin was quoted as saying.
Putin's hardline comments sit awkwardly with the reset in US-Russia ties championed by his successor in the Kremlin, President Dmitry Medvedev, which has seen a swift warming of relations over the last months.
Putin's comments came despite conciliatory remarks from US Defence Secretary Robert Gates, who praised Moscow for refusing to block military action against Libya as evidence of "extraordinary" progress in US-Russia ties.
Currently in Russia's second city Saint Petersburg, Gates heads to Moscow on Tuesday to meet his Russian counterpart, Anatoly Serdyukov, and President Medvedev.
However, conspicuously, there was no scheduled meeting with Putin for Gates' visit.