Prime Minister Dmitry Medvedev has ordered Russia's energy and trade ministries to conduct an inquiry within seven days into the cause of contamination that has led to the suspension of Russian oil deliveries to Europe through the Soviet-era Druzhba pipeline.
A Russian government statement on April 27 about the investigation says the results should be sent to the Russian Prosecutor-General's Office.
In Beijing, President Vladimir Putin said on April 27 that an inquiry must, "first and foremost," be conducted internally by Russia's state-owned oil transport monopoly Transneft, which operates the pipeline network.
Putin also confirmed that he has spoken with Belarusian President Alyaksandr Lukashenka about the disruption of Russian oil shipments to Europe through the Druzhba pipeline due to contamination.
Speaking to journalists on the sidelines of China's Belt and Road Forum, Putin described his conversation with Lukashenka as "a very brief exchange of views on this matter."
"I am aware of what happened, but the details are unknown to me because in order to understand what happened there, one needs to conduct an investigation," Putin said.
"First and foremost, it is necessary to conduct an investigation at the level of Transneft itself, and to identify the place from which it came from, for what reasons, what it was and so on," Putin said. "This investigation is ongoing."
"If an inquiry within the corporation is insufficient, I do not rule out that we will conduct an investigation involving law enforcement agencies and security services," Putin said.
Putin's remarks came hours after Russia announced it would be able to restore acceptable-quality oil supplies through the Druzhba pipeline to Europe in about two weeks.
Russian Deputy Prime Minister Dmitry Kozak said on April 26 after talks in Minsk with officials from Belarus, Ukraine, and Poland that the four countries had agreed on joint measures to eliminate the effects of the contamination that had forced the suspension of deliveries.
"This would allow us, as earlier planned, to supply...[uncontaminated] oil to the border with Belarus by April 29 and to restore the pipeline [to stability] in two weeks," Kozak said.
Poland and Belarus on April 19 announced they had stopped accepting shipments of Russian oil through the aging Druzhba pipeline, saying buyers in Poland and Germany could not accept the Russian crude because it is "contaminated" and of "poor quality."
Belarus has said that the source of "chlorine contamination" of the oil was found within Russia along the pipeline’s Samara-Unecha section.
Organic chloride is typically used by producers to increase crude oil output, but it must be separated before the crude oil is shipped to refineries because it can destroy refinery equipment.
Transneft said on April 26 that the contamination leading to the suspension of oil shipments to Europe could have been deliberate, and that a criminal case had been opened.
Officials from Russia’s Energy Ministry also met in Minsk with representatives of oil transport firms from Russia, Belarus, Poland, and Ukraine to discuss the issue.
Those four companies included Russia's Transneft, Belarus's Belneftekhim, Poland’s PERN, and Ukraine's Ukrtransnafta.
Russia's deputy energy minister, Pavel Sorokin, told reporters after the talks that one of the options for supplying clean oil was to mix the contaminated product with an untainted supply.
The Druzhba pipeline is the world’s longest oil pipeline and one of the world’s largest oil pipeline networks.
Originally built to supply oil to the western parts of the Soviet Union and former Soviet bloc countries in Eastern Europe, it is now the main export route for sending oil to Europe from Russia and Kazakhstan.
The suspension of deliveries through Poland is preventing major buyers from receiving Russian oil at their refineries in Poland and Germany -- including Poland’s PKN Orlen refineries and plants in Germany belonging to Total, Shell, BP, and Rosneft.
Western oil buyers say the suspension of oil flows could trigger a series of legal claims against Russian suppliers who, in turn, will likely seek compensation from Russia’s Transneft oil monopoly.
Belneftekhim’s deputy chief Uladzimer Sizou on April 26 estimated that losses were about $100 million.
Michael Lynch, an oil industry analyst who head the firm Strategic Energy and Economic Research, called the disruption of Russian oil deliveries "quite strange."
Lynch said the chlorine contamination could be linked to "technical problems at a Russian refinery."
"It has caused some nervousness in the markets, but it seems the situation can be resolved rapidly," Lynch said.