KIEV, September 27. /TASS/. Kiev is concerned of a huge reduction or a complete halt of gas transit to Hungary via Ukraine on the back of the long-term gas supply contract bypassing Ukraine inked between Budapest and Gazprom, CEO of the Operator of Ukrainian Gas Transport System Sergey Makogon wrote in Facebook on Monday.

"Despite the contract [on gas transit to Europe between Russia and Ukraine] by 2024, we expect a further significant reduction or a complete halt of transit to Hungary via Ukraine," the top manager said.

Hungary signed a new long-term gas supply contract bypassing Ukraine with Russian gas holding Gazprom, Reuters news agency reported earlier today.