Ukrainian President Volodymyr Zelenskiy was quoted by Interfax Ukraine news agency as saying on Wednesday he had no doubt that an explosion that killed two people in Poland was not caused by a Ukrainian missile.
"I have no doubt that it was not our missile," he was quoted as telling Ukrainian media.
He said he believed Tuesday's explosion was caused by a Russian missile, adding that he based his conclusions on reports from Ukraine's military which he "cannot but trust".
Zelenskiy was quoted as saying he believed Ukraine should already have been given access to the site of the explosion.
"Do we have the right to be in the investigation team? Of course," he said.
Zelenskiy also said Kyiv had received no offer from Moscow to start peace talks. Kremlin spokesman Dmitry Peskov said this week that Ukraine was not interested in holding peace talks with Russia.
"They do not communicate with us," Zelenskiy said.