Russian President Vladimir Putin and German Chancellor Angela Merkel agreed in talks in Brazil on Sunday that the situation in Ukraine, where Kiev is continuing an offensive against pro-Russian separatists in the east, is "deteriorating," the Kremlin said.

"Putin and Merkel had a constructive, very thorough dialogue during which they discussed in detail possible options for resolving the situation in Ukraine," Kremlin spokesman Dmitri Peskov told the Russian news agency Ria Novosti. "The two leaders agreed that unfortunately the situation is deteriorating."

House raids, bugging devices, threats, violence and demeaning posters are just a few things Vladimir Putin's critics have faced while trying to run for city parliament in the Russian capital.

Two years after President Putin was elected for a historic third term - facing mass protests in Moscow where less than half of the population voted for him - the Kremlin strongman is riding high in the polls while the opposition is all but stamped out.

President Vladimir Putin visited Russia's Cold War ally Cuba on Friday, launching a tour that will see him cozy up to Latin America amid newly frayed relations with the West.

Putin's six-day trip will also take him to Argentina and Brazil, where he will take part in a summit of the BRICS group of emerging countries -- an agenda that neatly aligns with his push for a multi-polar world at a time when the Ukraine crisis has brought Moscow-Washington relations to a post-Cold War low.

Russian President Vladimir Putin said Thursday he hopes to increase Russian investments in and trade with Latin America.

During a tour in Cuba that will also take him to Argentina and Brazil, the Russian leader said he was focusing on enhancing technological cooperation and investment, especially in the sectors of energy, nuclear power and machinery.

Russian President Vladimir Putin looks set to meet German Chancellor Angela Merkel amid tensions over Ukraine when both leaders attend the World Cup final in Rio de Janeiro, the Kremlin said Thursday.

Presidential adviser Yury Ushakov said the meeting had not been finalized but Putin was due to have a series of bilateral encounters with world leaders at the match on Sunday and that a tete-a-tete with Merkel appeared to be on the cards. 

Russia's popularity around the world is sagging, and so too is confidence in the way President Vladimir Putin handles global affairs, a 44-nation survey published Wednesday suggests.

In the wake of the Ukraine crisis, 74 percent of Europeans, 72 percent of Americans and 68 percent of Middle East respondents said they have unfavorable views of Russia, according to the Pew Research Center poll.

Russian Senate speaker Valentina Matviyenko said on Tuesday she abhorred Kiev's "scorched earth" tactics in eastern Ukraine, but that the Kremlin was unlikely to seek a new mandate for military intervention in the crisis.

"What is happening now is a scorched earth tactic, a purge of the territory in certain areas of eastern Ukraine that the National Guard has occupied," said Matviyenko, the speaker of the Federation Council and formally Russia's third most senior politician.

Russian prosecutors on Monday demanded eight-year jail terms for radical opposition leader Sergei Udaltsov and a fellow activist on charges of organizing mass riots to destabilize Vladimir Putin's rule.

Udaltsov's lawyer Violetta Volkova said prosecutors were seeking eight-year jail terms for him as well as co-defendant Leonid Razvozzhayev. "Eight years for each," she said on Twitter.

Russian President Vladimir Putin "can be dangerous" and will always push other political leaders as far as he can, former U.S. secretary of state Hillary Clinton told a German newspaper Sunday.

"A man like Putin always goes to the limits. He always tries to find out how strong the others are" and then re-positions himself accordingly, she told Bild am Sonntag.

Russia's President Vladimir Putin congratulated U.S. counterpart Barack Obama on America's Independence Day Friday and expressed hope that bilateral relations would "successfully develop" despite their disagreements.

Putin predicted that relations between Russia and the United States "will successfully develop on a pragmatic and equal foundation despite the difficulties and differences," the Kremlin said.