Mateusz Morawiecki was speaking in Brussels before a two-day summit of EU leaders, Polish state news agency PAP reported.
EU leaders meeting in the Belgian capital were set to discuss support for Ukraine in response to Russia's invasion, in addition to a range of defence, energy and food security issues.
Ukraine’s President Volodymyr Zelensky was expected to address the gathering via video link.
'Let’s stop buying oil from Russia'
Morawiecki told reporters in Brussels: “The sixth package of sanctions that we’ll be discussing here today must include our most far-reaching demands.”
He added: "We are demanding that oil should be part of the 6th package. Let’s stop buying oil from Russia - this is our core demand."
He called on the bloc "to cut Russia off from income that allows it to wage this war."
'Compromise can be reached’
Morawiecki said that the European Commission was trying to "forge a compromise on this issue to get all EU members on board."
Brussels has proposed phasing out Russian oil supplied by sea by the end of 2022, the Reuters news agency reported.
Oil delivered by pipeline to landlocked Hungary, Slovakia and the Czech Republic would be exempt from the embargo, officials said.
“We understand that some countries are landlocked and need to receive oil via pipelines,” Morawiecki said. "We have special arrangements for them."
He added that “if these countries, including Hungary, do not accept these arrangements,” then “Poland will demand a special price equalisation mechanism.”
This measure would be designed so that those who are allowed to buy Russian oil longer “don’t have a competitive edge over others,” Morawiecki told reporters.
He said he believed that “it is possible to reach some sort of compromise here at the European Council summit.”
A show of unity against Putin
Such a comprise would show Russia's Vladimir Putin that “we are united and highly determined to bring this war to an end as soon as possible; and for Ukraine to survive as a free, sovereign, independent country,” Morawiecki told reporters.
Monday was day 96 of the Russian invasion of Ukraine.
(pm/gs)
Source: PAP, wiadomosci.wp.pl