Russian President Vladimir Putin has dismissed criticism over a police crackdown on protesters, saying anyone who breaks the law will be punished.
In remarks on March 30, Putin suggested that opposition leader Aleksei Navalny was using the rallies to promote himself ahead of the country's 2018 presidential election.
On the same day, the Moscow City Court upheld a 15-day administrative jail sentence against Navalny, who was charged with resisting a police officer on the day of the March 26 protests.
Putin's remarks were his first public comments on the anticorruption rallies that brought tens of thousands of people into the streets in dozens of cities across Russia four days earlier, the biggest protests against his government in about five years.
Police detained more than 1,000 people in Moscow alone, beating some of them in a show of force.
Clearly referring to protest organizer Navalny without naming him, Putin said it is "wrong when somebody, some political forces try to use this [fight against corruption] in their own sordid interests, not to improve the situation in the country but for self-promotion in the political arena on the eve of...election campaigns."
Speaking at a meeting on Arctic issues in the northern city of Arkhangelsk, Putin said that "everybody who goes beyond the bounds of the law, including those at the public gatherings, must be punished in accordance with Russian law."
Putin said that corruption is a "rather serious problem for us as for other countries."
Putin also dismissed criticism from foreign governments over the crackdown, saying "we consider appeals of this sort to be purely politicized questions with the goal of putting some kind of pressure on the internal political life of the country."
Navalny announced in December that he would run for president in a March 2018 election in which Putin is widely expected to seek a new six-year term.
The March 26 rallies were prompted after Navalny's organization released an investigative report with compelling allegations of massive corruption on the part of Prime Minister Dmitry Medvedev. Navalny has campaigned unsuccessfully to force the government to investigate the allegations.
Initially, the government and state media largely ignored the mass protests. Kremlin spokesman Dmitry Peskov on March 27 speculated that many of the young participants in the demonstrations had been paid to attend.
Prosecutors have opened an investigation into that allegation.
On March 30, Peskov called the demonstrations a "provocation," but added that the government has "no information" that they were funded from abroad.
Peskov declined to answer a question regarding Putin's relationship to Medvedev in the wake of Navalny's exposé.
In addition to Navalny, 12 members of his anticorruption organization have been given short administrative jail sentences following the March 26 protests.
A spokeswoman for the Anticorruption Foundation said the arrests were "an obvious attempt to disrupt the work of the organization."
After Navalny's sentence was upheld on March 30, Olga Mikhailova, a lawyer for the detained opposition leader, said she would be taking his case to the European Court of Human Rights.
Russia ranks 131st of 176 countries in the Corruption Perception Index of the international NGO Transparency International.
According to a 2011 report by the Global Financial Integrity think tank, Russia lost $427 billion to corruption between 2000 and 2008.
With reporting by AP, DozhdTV, Interfax, TASS, RIA Novosti, and Ekho Moskvy