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US Defence Secretary Lloyd Austin will host Ukraine-focused defence talks with allies at Ramstein Air Base in Germany next week, the Pentagon said.
About 40 countries were invited to participate in the talks looking at Ukraine's long-term defence needs. So far, 20 countries have agreed to attend, Pentagon spokesman John Kirby said.
"The RSVPs are still coming in, but I can tell you that more than 20 of the invited nations have agreed to come," Mr Kirby said.
Mr Kirby stressed the "Ukraine Defence Consultative Group” gathering on April 26 remains outside of Nato, with some non-Nato members invited to attend.
“Nato as an alliance is not providing security assistance to Ukraine. This is not being done under the Nato umbrella at all,” Mr Kirby said.
While some of the attendees are Nato members, they’re participating unilaterally, the Pentagon said.
Mr Kirby appeared to play down expectations of announcements about long-term assistance at the talks, saying: "We're not going into this with a pre-cooked set of endings here.”
Discussions will include the latest battlefield assessments of the renewed Russian offensive in eastern Ukraine, how countries can energise the defence industrial base to continue the steady flow of weapons to Ukrainian forces and a larger view of Kyiv’s defence needs stretching beyond the current war with Russia.
The US and at least 30 other countries have helped provide Ukraine with military assistance since the Kremlin’s attack began on February 24.
Mr Kirby said on Friday the US “has helped co-ordinate and deliver more than 50 million rounds of small arms ammunition to Ukraine just since the invasion".
Reuters contributed to this report