Ukraine may run out of gas. Kyiv needs to increase its reserves, but this will be expensive.

This is the fourth winter Kyiv will have to face threats of energy shortages. Moscow regularly attacks civilian infrastructure in an attempt to "freeze" Ukrainians .

The Kremlin's attack also resulted in a significant reduction in gas production, as the Russians have occupied and continue to occupy some Ukrainian gas fields. Therefore, gas reserves are crucial for Kyiv.

As reported by Reuters, Ukraine has secured gas reserves to cover 80-90% of its winter demand and needs up to $1 billion in additional fuel to survive the fourth heating season since Russia invaded the country.

Ukraine has about 11 billion cubic meters of gas in storage, which is over 80 percent of the government's target of 13.2 billion cubic meters, Yuriy Boyko, a member of the supervisory board of state-owned electricity grid operator Ukrenergo, recently admitted.

The Ukrainian consulting firm ExPro presented slightly different results regarding the state of reserves, estimating them at 12 billion cubic meters, or 90% of the target. The difference may be due to the adopted measurement methodology.

However, there is no doubt that Ukraine will need even more gas for the heating season .

This means 1-2 billion cubic meters will have to come from domestic production or be imported from other European countries, officials and analysts say.

According to Reuters calculations, based on current and last year's EU gas prices, this would cost the country between $500 million and $1 billion.

Officials warn that further attacks on production facilities or warehouses could force Ukraine to shift its targets. Last winter, power outages lasted up to 18 hours a day in some regions.

For Kyiv, Poland could be a key supply destination. Poland and Ukraine are connected by a gas interconnector. The key question, however, is where Kyiv will get the additional gas and how it will pay for it.