Speaking on Serbian TV channel, Vucic said that due to the escalation of the conflict in Ukraine, conversations with Western representatives have become more demanding and tough, including on the settlement in Kosovo.
"I was told: 'We have a war under way in Europe, we are participating, though we don't say it.' And they say that we [Belgrade] will lose a lot or everything unless we behave properly," he said.
Vucic said Western officials announced a possible termination of investment in Serbia, withdrawal of already invested capital, shutdown of enterprises and suspension of its European integration if Belgrade remains intractable.
The Serbian leader earlier said the West is increasing pressure on his country due to Belgrade's refusal to support anti-Russian sanctions.
After the start of Russia's special military operation in Ukraine more than a year ago, the West stepped up sanctions pressure on Russia, which led to an increase in prices for electricity, fuel and food in Europe and the US.
Russian President Vladimir Putin earlier said the policy to contain and weaken Russia is a long-term strategy for the West, and sanctions have dealt a severe blow to the entire global economy. According to him, the main goal of the West is to make the lives of millions of people worse. Russia has repeatedly said it will solve all the problems the West creates for it.