From the Washington Post:
His response was unequivocal. “The terms of presidential authority will not be changed under the current president,” Vladimir Putin said in 2001, his second year in office, arguing that amendments to the constitution “dictated by political considerations” were dangerous. “Even in the most difficult times and times of crisis,” he said, “those in power did not succumb to the temptation to correct the constitution for themselves. In the end, this was for the good.” Putin repeated the pledge on the eve of his second term, saying the constitution should be left “untouched.”
Now, months after leaving office and becoming prime minister, Putin is helping another relatively young, newly elected Russian president do exactly what he promised never to do himself — rewrite the constitution to extend the presidential term. The abrupt reversal has sparked speculation in Moscow about whether Putin is preparing to take back his old job as president, and why.