Ukrainian President Volodymyr Zelenskyy is applying more pressure on President Donald Trump to increase the cost of what he sees as Russian obfuscation.

Russian and Ukrainian delegates met in Istanbul on Monday for their second set of direct peace talks, a day after Kyiv launched a shock drone attack on Russia’s nuclear-capable bombers, in an operation that President Volodymyr Zelensky said was a year and a half in the making.

Russian and Ukrainian officials are due to hold peace talks in Istanbul with no sign they are any closer to an agreement.