The Kremlin is planning an armed incursion on Polish land to test Nato's response, according to Washington.The provocation could see Putin's troops cross over into Poland, and vital infrastructure could be targeted by missiles and drones.Sources close to Polish President Karol Nawrocki told news outlet Onet that the US had been warning Warsaw about the plan for a while.Russia's plan aims to start a crisis to scare Western nations into stopping their support for Ukraine. Polish security experts also warned that Russia and Belarus might send a small number of troops across the Nato border.Power stations could also be targeted in the incursion, through air strikes that would force Poland to activate its air defence systems.According to Polish sources cited by Onet, Russia could frame a territorial incursion as either a GPS navigation error or an emergency helicopter recovery. Moscow's strategy relies on the assumption that the US would compel Poland to negotiate rather than engage militarily. Polish soldiers move ashore from a military motorboat during the Bursztynowy Obronca-26 (Amber Defender-26) military exercise in June 2026 Polish soldiers ride in a military motorboat during the Bursztynowy Obronca-26 (Amber Defender-26) military exercise in June 2026 The provocation could see Putin's troops cross over into Poland , and vital infrastructure could be targeted by missiles and dronesA peaceful, negotiated retreat would be treated as a strategic win for the Kremlin, which could leverage the talks to demand a halt to Western military assistance for Ukraine. And in a worst-case scenario for Nato, Russia would aim to undermine Polish sovereignty, force the withdrawal of Western support for Ukraine and expose Nato as a paper tiger.According to sources, a ground-based attack could come from Kaliningrad - which borders northern Poland - or from Belarus to the east.Russia depends on targeted, limited provocations to probe Nato's defences, as its military is too heavily committed in Ukraine to launch a major war. Although Poland is a vital security partner for Ukraine, their alliance has recently fractured over agricultural trade and past historical grievances. Moscow is expected to try to worsen this divide A source close to the Polish president said that the US 'systematically informs Poland about ever-new Russian plans for a conventional attack on Nato's eastern flank, from which Poland is by no means excluded.'Two separate sources - an ambassador to one of Poland's allies in the Nato alliance and a source in the Polish defence ministry - also confirmed that there is a serious risk of an incursion in Poland and the Baltic States.However, European security sources also said that a provocation targeting Poland would be more useful than targeting the Baltics. Speaking to The Telegraph, a Baltic security source said Moscow was currently discussing these plans. Russia reportedly may attempt to pin the provocation on Ukraine after it is carried out. A recent naval exercise in Latvia, in which the US Navy and Marines participated, is understood to have been designed to remind Putin that an attack on the eastern flank would be seen as an attack on US troops.Poland has conducted similar exercises, according to a member of the Polish ministry's defence leadership. Nato could respond to the attacks by attacks on Kaliningrad, it is understood, which German air force chief Holger Neumann has cited as a potential target. He also singled out the Kola Peninsula, where Moscow holds nuclear weapons, and the Black Sea as potential targets. Speaking to The Telegraph, Neumann vowed that Germany would defend 'every inch' of Nato territory, including Poland if needed. Polish President Karol Nawrocki (C) meets with soldiers of the Polish Military Contingent A Polish soldier kneels next to a military vehicle during the Bursztynowy Obronca-26 (Amber Defender-26) military exercise in June 2026Meanwhile, Ukraine's top military commander also said in an interview broadcast on Tuesday that his forces were preparing for a possible new Russian attack from the north, but any attempt to advance on Kyiv was unlikely.Oleksandr Syrskyi, interviewed on TSN Ukrainian television, also said an attack from neighbouring Belarus was unlikely after weeks of Ukrainian allegations that Moscow was trying to press its ally to play a greater role in the war.'The most likely scenario, and this is confirmed by several data sources, is possible offensive action in the north from the territory of Russia, from the Bryansk region,' Syrskyi said.'This is a realistic option, of course, and we are preparing for it.'The aim of such an operation, he said, was not to try to move on Kyiv as Russian forces had attempted to do after their February 2022 invasion before withdrawing and focusing on the Donbas region in the east.Instead, they would try to seize territory in Ukraine's Chernihiv region and draw Ukrainian forces engaged elsewhere along the 775-mile front line.Such a strategy would amount to 'stretching the front and depriving us of reserves'.But Belarus, which allowed Russian President Vladimir Putin to use its territory in launching his initial push into Ukraine, was unlikely to agree to further involvement, he said.Last month Zelensky gave Belarus, under veteran President Alexander Lukashenko, a week to dismantle relay stations Kyiv he said were being used to attack Ukraine. Zelensky has since said the stations are no longer operating.In his comments to the broadcaster, Syrskyi also said there were indications that Russian troops were exhausted and the intensity of frontline battles was declining.He said Russian frontline activity had declined by 30 per cent while Ukrainian forces pressed on with a campaign of long-range strikes against Russian targets, mainly linked to the oil industry.