It will be a challenge for <a href="https://www.thenationalnews.com/tags/nato/" target="_blank">Nato</a> countries to continue supplying Ukraine with lethal aid while also having troops on high alert if the war drags on for many more months, Germany’s ambassador to the UK has said. Following discussions at the military alliance’s summit in Madrid last week members pledged to donate more weapons to Ukraine in response to pleas from<a href="https://www.thenationalnews.com/tags/volodymyr-zelenskyy/" target="_blank"> President Volodymyr Zelenskyy.</a> Nato leaders have agreed to put more than 300,000 troops on high alert from mid-2023, up from 40,000 currently, to counter Russia. The US put forward an $820 million (£677 million) bundle, which includes new surface-to-air missiles and counter-artillery radars, to respond to Russia’s heavy reliance on long-range strikes in the conflict. Britain promised an extra £1 billion ($1.3 billion) in military aid, while France agreed to deliver six more self-propelled Caesar long-range artillery systems. Germany promised to send 15 anti-aircraft tanks to Ukraine in July after repeated delays. Asked about Germany’s sluggish response to calls from Kyiv to send weapons, Miguel Berger, Berlin’s man in London, acknowledged “we always can and we have to do more.” “My concern is really that we as Nato, as [a] Western alliance, we have to be capable of supporting Ukraine if this war drags on for weeks and months,” Mr Berger told Sky’s <i>Sophy Ridge on Sunday</i>. “And that will be also a challenge for our armed forces.” He touched on the possibility of the war descending into a “deep freeze” if Russia captures all of the eastern Donbas region of Ukraine and pushes further into the south. “I think it’s one of the possible outcomes of this terrible war that we might go into a deep freeze,” he said. Mr Berger said if Moscow’s forces make further gains in the Donbas their next target could be the strategic southern port city of Odesa. “Putin is watching very closely the unity of the western alliance,” he added. “But I think the messages which came out of the G7 summit [and] the Nato summit with the 300,000 troops now on heightened alert, I think that at least has sent a very strong message towards Russia.” In other developments, <a href="https://www.thenationalnews.com/tags/olaf-scholz/" target="_blank">German Chancellor Olaf Scholz </a>said his government is discussing security guarantees for Ukraine with its allies, in preparation for a time after the war in Ukraine. “We are discussing with close friends the question of the security guarantees we can give. This is an continuing process. It is clear that it will not be the same as if someone were a member of Nato,” Mr Scholz told the broadcaster ARD on Sunday. “It is quite clear that this is a matter which is being carefully prepared in the diplomatic sphere, for the day we hope to see soon, when the war is over,” he added. Czech Prime Minister Petr Fiala on Sunday said the country’s fighter jets will guard neighbouring <a href="https://www.thenationalnews.com/tags/slovakia/" target="_blank">Slovakia</a>’s air space from September. Slovakia asked its Nato allies to patrol its skies as it decided to ground its Russian-made MiG-29 fighter jets, which could be sent to neighbouring Ukraine to help Kyiv defend itself against Russia's invasion. “I don't see any problem there, the government will certainly approve it,” Mr Fiala said in a televised debate with his Slovak counterpart Eduard Heger. Slovakia ordered F-16 fighter jets from the US in 2018. The first planes were expected to arrive this year and the shipment to be completed in the next year, but the delivery is now expected to take place in 2024. Russia claims to have captured the city of Lysychansk, the last Ukrainian stronghold in Luhansk. Russia’s defence chief told President Vladimir Putin that Moscow’s troops had taken the city, state media reported on Sunday, following <a href="https://www.thenationalnews.com/world/europe/2022/07/02/russian-forces-strike-key-city-of-lysychansk/" target="_blank">heavy shelling on Saturday.</a> The move would put Russia closer to its goal of controlling Ukraine’s entire Donbas region, which covers Luhansk and Donetsk. Ukraine’s government has not yet commented on the claim.