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The UK wants modern weapons to be sent to Moldova to prevent Russian President Vladimir Putin’s ambition for a “greater Russia” from becoming a reality.
“I would want to see Moldova equipped to Nato standard. This is a discussion we're having with our allies,” she told The Telegraph.
“Putin has been absolutely clear about his ambitions to create a greater Russia. And just because his attempts to take Kyiv weren't successful doesn't mean he's abandoned those ambitions.”
A month ago, a series of explosions in Transnistria, Moldova's Russian-backed separatist region, raised fears in the West fighting would spill over from Ukraine.
“What we're working on at the moment is a joint commission with Ukraine and Poland on upgrading Ukrainian defences to Nato standard,” she said.
“So we will scope out what that looks like, what the Ukrainians need. The question then is how do you maintain that over time?
“How do we ensure that there is deterrence by denial, that Ukraine is permanently able to defend itself and how do we guarantee that happens? That's what we are working on at the moment.
“And that also applies to other vulnerable states such as Moldova. Because again, the threat is broader from Russia, we also need to make sure that they are equipped to Nato standards.”
If Ms Truss's plans are adopted, Nato members would provide modern weaponry to Moldova, replacing its Soviet-era equipment, and will train soldiers on how to use it.
On May 4, European Council President Charles Michel pledged to increase EU military aid to Moldova, which applied to join the bloc in March.
Transnistria used to be part of a Russian-speaking area of Ukraine, while the rest of Moldova has Romanian heritage.
Ethnic Russians and Ukrainians outnumber ethnic Moldovans. Transnistria is not internationally recognised, but Russia has been its prime supporter.
Russia recognised the two breakaway regions in Ukraine, Donetsk and Luhansk, days before the invasion force swung into action. The regions have experienced some of the fiercest fighting.
Since the war in Ukraine, Finland and Sweden have applied to join Nato.
Moldova, a country of about 2.6 million, has taken in 468,998 refugees from Ukraine.