Russia said Saturday that new European Union sanctions targeting Russian intelligence chiefs over its role in Ukraine risked ending all joint cooperation on security.

The European Union "has practically speaking put at risk international cooperation in the area of security," the Russian foreign ministry said in an angry response.

The European Union is making swift progress on adopting much tougher economic sector sanctions against Russia for its role in the Ukraine crisis, officials said Friday.

After discussions on broadening the sanctions from the current mix of asset freezes and travel bans, the legal instruments required to give effect to the new punitive measures will be taken up Tuesday, they said.

A strip of white bandage on a stick in a sunflower field marked the spot where the remains of one of the 298 victims of downed Malaysian flight MH17 lay in the sun on Friday more than a week after the crash.

Combine harvesters cut down the wheat in surrounding fields in a semblance of normality at the gruesome scene -- some of them skirting pieces of the wreckage.

Russia on Friday called the latest U.S. accusations of Moscow's involvement in the Ukrainian conflict a baseless "smear campaign" and said Washington bears responsibility for the bloodshed.

"Due to the smear campaign against us that the U.S. Administration has begun... we reject the unfounded public insinuations that U.S. deputy State Department spokeswoman Marie Harf is spreading on a daily basis," a statement by the Russian foreign ministry said. 

An American "peace ambassador" traveling around the world on his bicycle was run over and killed by a Russian drunk driver in a hit-and-run accident, officials said Friday.

Ron McGerity, a 60-year-old who had traveled 120,000 kilometers (75,000 miles) over the past 15 years on his bike visiting 61 countries with a message of peace, died on Thursday on a country road in central Russia.

Ukraine's political circus made an unwelcome return to center stage as bickering lawmakers struggled Friday to avert a crisis of their own making after Prime Minister Arseniy Yatsenyuk resigned in a huff.

As the country battles a bloody pro-Russian insurgency in the east amid international attention over the downing of Malaysia Airlines flight MH17 and teeters on the brink of bankruptcy, analysts said the last thing Ukraine needed was a bout of political limbo.

The Polish government has canceled plans for a year of cultural celebrations with Russia out of anger with Russian actions in Ukraine.

The Foreign Ministry said Thursday that it summoned the Russian ambassador to inform him of the decision.

Russian opposition leader Sergei Udaltsov began a hunger strike on Friday, a day after being sentenced to four-and-a-half years in prison for inciting public unrest.

"Today is the first day of the indefinite hunger strike declared by Udaltsov. He is in Prison Number One and has been transferred to a solitary cell," said the Twitter blog formerly kept by Udaltsov and now updated by his allies.

The European Union is making swift progress on adopting much tougher economic sector sanctions against Russia for its role in the Ukraine crisis, officials said Friday.

After discussions on broadening the sanctions from the current mix of asset freezes and travel bans, legislative proposals required to give effect to the new punitive measures will be taken up Tuesday, they said.

Ukraine sought Friday to avoid a political crisis after the shock resignation of its prime minister, as fighting between the army and rebels close to the Malaysian airliner crash site claimed over a dozen more lives.

President Petro Poroshenko called on parliament to heed "cold reason" and pass a vote of confidence in the government, a day after premier Arseniy Yatsenyuk walked out in fury over the collapse of his ruling coalition.