An expert has warned that Vladimir Putin may leverage his potential victory in Ukraine to issue "open ultimatums" to non-NATO countries.

       Vuk Vuksanovic, a political scientist and associate at LSE IDEAS, said that two non-members would be particularly at risk of receiving such threats.

       He claimed that Moldova and Georgia, who have historically remained neutral countries and not joined NATO, would likely face Putin's ultimatums.

       Vuksanovic explained that Putin would seek to exert his power over those two countries in particular in order to isolate them from Western allies, forcing them into a closer relationship with Russia.

       He told Daily Express US: "Putin might use his victory in Ukraine as a way to issue an open ultimatum to Moldova and Georgia and force their governments to cut security ties with the West and align their foreign policies with Moscow."

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       Vuksanovic added that Putin does not possess the "capacity or ambitions" to go after NATO countries that come with higher risks as other members would be forced to intervene.

       He would instead opt for Moldova and Georgia in order to tighten his grip over the region without triggering "NATO's collective defence mechanism".

       Vuksanovic added: "The chances that Russia would go into a NATO member state are even more remote. Russia does not have the capacity or ambitions to attack a NATO member state like Poland, nor is it willing to risk the activation of NATO's collective defence mechanism."

       This comes as Russian forces are gearing up for a summer offensive, particularly targeted at the Eastern region of Ukraine, as they aim to capture Kharkiv - Ukraine's second largest city.

       Oleksandr Pivnenko, the commander of Ukraine's National Guard, warned that his troops are preparing for "unpleasant surprises" as Russia aims to strike them where they least expect it.

       He told the Ukrainian Liga.net news outlet: "We are getting ready. It will operate in areas where we do not expect, but it will not achieve its goal."

       Volodymyr Zelensky has issued repeated desperate pleas for more military assistance, particularly from the US, stressing that his country will be defeated without it.

       As a result, Joe Biden finally signed into law a $61 billion (￡48 billion) aid bill for Ukraine, expected to contain air defence capabilities, artillery rounds, and armoured vehicles to help secure a decisive victory and prevent Russian escalation.