Ukraine has carried out large-scale drone strikes against four airbases deep inside Russia, destroying multiple combat planes, according to a source in the Ukrainian Security Service (SBU).

Ukrainian negotiators at talks scheduled for June 2 in Istanbul will present to the Russian side a proposed roadmap for reaching a lasting peace settlement, according to a copy of the document seen by Reuters.

At least seven people were killed and 69 injured when two bridges were blown up in separate Russian regions bordering Ukraine ahead of planned peace talks.

Two bridges have collapsed in Russia’s western regions bordering Ukraine, killing multiple people and injuring dozens, authorities said.

By making harsh, uncompromising demands in peace talks with Ukraine while continuing to pummel it with waves of missiles and drones, Russian President Vladimir Putin is sending a clear message: He will only accept a settlement on his terms and will keep fighting until they’re met.

At least seven people were killed after Russian officials said “illegal interference” caused a bridge to collapse and a train to derail in Russia.

With Russia saying its terms for peace must remain secret until the talks begin, Ukraine won’t confirm whether its delegation will even attend.