Moscow (CNN) Russian President Vladimir Putin touched a political third rail on Wednesday, and it had nothing to do with election meddling, Cold War theatrics or his relationship with US President Donald Trump.

No, it was a pocketbook issue: the Russian government's proposed overhaul of the country's pension system

In a rare address to the nation, Putin took to the airwaves to defend the deeply unpopular new proposal to raise the retirement age, a measure that has dented his popularity and spurred calls for protests.

"The conclusion is clear," Putin said. "The active working-age population is decreasing, along with our capability to pay and adjust pensions for inflation. Therefore, changes are necessary."

Putin makes an address on state TV Wednesday to make the case for raising the retirement age.

It was a buck-stops-here moment for Putin, who said the country "will inevitably face serious demographic problems" by the next decade if there are not changes to Russia's retirement system.

But the speech also underscored that Putin's popularity is not bulletproof.

Putin, who has dominated political life in Russia for 18 years, has enjoyed sky-high approval ratings, and his confrontations with the West often shore up his domestic political support. But Putin is not a Teflon President when it comes to domestic policy matters.

Protests in the streets

The government's proposal to raise the pension age prompted unusual street protests, with demonstrators taking to the streets earlier this summer to express their opposition to the government proposal to reform the pension system, a legacy of the social safety net Russia inherited from the Soviet Union.

Putin's approval ratings, routinely hovering around 80%, dipped in July to 67%, independent pollster Levada-Center found.

Putin, who had previously been on the record opposing any tweaks to the pension system, initially distanced himself from the proposed changes. The government of Prime Minister Dmitry Medvedev rolled out the package of legislation on the same day as the start of the 2018 FIFA World Cup, effectively burying the bad news amid the fanfare of the tournament.

In his Wednesday remarks, Putin renewed the case for the proposed reforms, but outlined a number of measures to soften their impact. Among other measures, Putin called for raising the retirement age for women to 60 from 55, instead of to 63.

A woman holds a poster protesting an increase in the pension ages from the current 60 to 65 for men and from 55 to 63 for women during a rally in Moscow on August 21.

"It is not right" to raise the pension age for women by eight years, Putin said. "In our country there is a special attitude to women, a caring one. We understand that they not only work at their main place of work, they usually run the whole house, caring for the family, raising children and fussing over their grandchildren."

It remains to be seen if that revision will satisfy Russians. A proposed five-year increase in retirement age for men, to 65, remains intact. The average Russian male life expectancy is 66, according to the World Health Organization.

In his speech, Putin in part blamed the rising burden on the pension system on the post-Soviet economic collapse of the 1990s, when Russian birth rates dropped. The Russian leader compared the "demographic collapse" of the late 1990s to the impact on population growth caused by World War II.

Critic arrested

Aleksei Kudrin, a former finance minister who heads Russia's audit chamber, praised Putin for offering a "balanced, carefully thought-out solution" that made necessary revisions to the original proposal.

The government may be keen to reverse the impact of long-term population decline, but it also appears to want Russians off the streets. On Monday, a Moscow court sentenced Russian opposition leader Alexei Navalny to 30 days of administrative arrest for organizing an unsanctioned rally in the capital in January.

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Navalny had called for nationwide protests on September 9 against an unpopular government proposal to raise Russia's retirement age, and in a statement on Twitter that followed Putin's speech, Navalny urged his supporters to turn out for the protests, which occur on the same day as local elections in Russia.

"Well, if this decision does not seem to you to be 'balanced and carefully thought-out,' then go out on Sept. 9 to protest against raising the retirement age," Navalny tweeted.

The proposed changes to the pension system come as the Russian government braces for possible new US sanctions that threaten to hit the ruble and the spending power of ordinary Russians.

But once again, those sanctions may not translate to diminished support for Putin: A recent Pew Research Center study found that an overwhelming majority of Russians -- 85% -- think it is the US that interferes in the domestic affairs of other countries.