NATO envoys hold emergency meeting after deadly missile strike in Poland | Le Monde |

The explosion in Poland, a NATO member, immediately sparked concerns that the alliance might be drawn directly into Russia's nearly nine-month war against Western-backed Ukraine.

UN Secretary-General Antonio Guterres, also in Bali, warned it was "absolutely essential to avoid escalating the war in Ukraine".

European Union chief Charles Michel said he was "shocked," and US Secretary of State Antony Blinken pledged to "remain closely coordinated in the days ahead as the investigation proceeds and we determine appropriate next steps."

'Significant escalation'

Ukrainian President Volodymyr Zelensky had earlier said two Russian missiles hit Poland in what he described as "a very significant escalation." Ukraine's Foreign Minister Dmytro Kuleba rejected as a "conspiracy theory" the idea that the Poland blast may have been caused by a surface-to-air missile fired by Kyiv's forces.

Russia's defence ministry meanwhile dismissed reports that it was to blame as a "provocation" intended to escalate tensions.