Vladimir Putin believes he has a strong hand ahead of a phone call Monday with Donald Trump and European leaders are trying to prevent the U.S. president from rushing through a deal.

Putin is confident that his forces can break through Ukraine’s defenses by the end of the year to take full control of four regions that he has claimed for Russia, according to a person familiar with the Russian president’s thinking who asked not to named discussing private conversations.

That means the Russian president is unlikely to offer any meaningful concessions to Trump when the two leaders speak and European officials are worried that Trump may try to force through a settlement regardless.