The European Union on Tuesday called on Azerbaijan to stop its military operation in the disputed region of Karabakh.
"Devastating news coming from former Nagorno-Karabakh oblast today," Michel wrote in a social media post, Barronís reported.
"Military actions of Azerbaijan must be immediately halted to allow for a genuine dialogue between Baku and Karabakh Armenians."
EU foreign policy chief Josep Borrell said the bloc "condemns the military escalation" and "deplores the loss of lives".
"This military escalation should not be used as a pretext to force the exodus of the local population," Borrell said.
"Violence needs to stop in order to provide a conducive environment for peace and normalization talks."
The EU has mediated talks with Azerbaijan and Armenia aimed at securing a lasting peace between the ex-Soviet foes.
Azerbaijan on Tuesday launched a military operation in its breakaway Karabakh enclave, nearly three years after fighting a brief but brutal war with Armenia over the mountainous region.