He also described the killing of top Kremlin critic Boris Nemtsov as "tragic and shameful" and said he wasn't certain if the Russian law-enforcement agencies would be able to track down those who organized the attack.
He focused heavily on economic issues, saying the nation's economic performance has remained strong, despite Western sanctions slapped on Russia over the Ukrainian crisis and a slump in global oil prices. He pointed at the ruble's recovery as a sign of a renewed investor confidence in Russia.
Putin, whose approval ratings top 80 percent despite the recession, said the country can overcome any challenges if it remains united.
"If we preserve a stable situation in domestic politics, preserve the current consolidation of society, we shouldn't fear any threats," he said.
Turning to foreign policy issues, Putin said his decision to lift a 2010 Russian ban on the delivery of the powerful S-300 air defense missile system to Iran followed a tentative deal on ending the Iranian nuclear standoff reached by Tehran and six world powers earlier this month.
He said Iran should be rewarded for showing "a great degree of flexibility and a desire to reach compromise" in the talks. He said the S-300 is a defensive weapon.
Putin said that Russia-West ties, which are in shambles over the Ukrainian crisis, could be normalized if the West shows a willingness to compromise and respect Moscow's interests, AP reported.
He also criticized Ukraine, accusing it of violating its obligations under February's peace deal by maintaining an economic blockade on rebellious eastern regions, refusing to deliver pensions and other social payments to people in the east, and shutting financial services to the region.
Putin argued that the Ukrainian leadership is effectively cutting off the eastern regions from the rest of the country. At the same time, the Russian president insisted that he remains committed to cooperating with the Ukrainian president to overcome the crisis, adding that the Minsk agreement signed in February provides the only way out of it.
He reaffirmed a strong denial of Ukrainian and Western claims that Russia has sent troops to back the rebels in eastern Ukraine.