MOSCOW (Reuters) - Russian President Vladimir Putin condemned weekend protests demanding the release of jailed Kremlin critic Alexei Navalny as dangerous and illegal, as the opposition politician’s allies said they planned a similar protest for Sunday. Police detained more than 3,700 people and used force to break up rallies across Russia on Saturday as tens of thousands of protesters ignored extreme cold and police warnings to demand Navalny be freed from jail where he is serving out a 30-day stint for alleged parole violations he denies. Putin, who avoids mentioning Navalny by name, told students on Monday that nobody should use illegal protest action to further their own political interests. “Everyone has the right to express their point of view within the framework provided by the law. Anything outside the law is not just counter-productive, but dangerous,” said Putin. He cited upheaval caused by the 1917 Russian Revolution and the 1991 collapse of the Soviet Union as examples of how illegal action could cause misery to people and should therefore best be avoided. As Putin was speaking, Leonid Volkov, a close ally of Navalny currently outside Russia, announced plans for a new protest this Sunday that would once again ask the authorities to free Navalny. Putin, in a rare public rebuttal of something Navalny has accused him of, on Monday rejected an accusation made in a video last week that has since gained more than 86 million views on YouTube. Navalny alleged in it that Putin owned an opulent Black Sea palace that the Russian leader’s friends had paid for, sometimes using public money. “I haven’t watched the film, simply because I don’t have the free time to watch such information, but I scrolled through video compilations,” Putin said. “...Nothing of what was indicated there as my property belongs either to me or to my relatives and never has belonged (to us). Never,” he said. Tensions between Moscow and Washington have flared over the Navalny protests. Russia’s Ministry of Foreign Affairs said on Monday it had issued a diplomatic protest to U.S. Ambassador to Russia John Sullivan over what it said it regarded as interference in its domestic affairs. It said it took exception to social media posts by the U.S. embassy which it alleged supported the illegal protests and to what it called an unacceptable stance from the State Department. The United States on Saturday condemned what it described as “harsh tactics” used against protesters and journalists and called for Navalny’s “immediate and unconditional” release. Putin will address the World Economic Forum by video conference on Wednesday, Russian news agencies cited the Kremlin as saying. The appearance is likely to be contentious with critics at a time when the West is weighing possible new sanctions against Russia over its treatment of Navalny.