KYIV, Ukraine: Ukraine announced Monday it had received more air defence systems from Western military allies, as officials in Kyiv asked residents to use electricity sparingly after weeks of Russian attacks on energy facilities.The new weaponry comes as a question mark hovers over American support for Ukraine ahead of elections on Tuesday which will determine control of the US Congress.Republicans, who analysts say will win the House of Representatives and perhaps the Senate too, have expressed concerns about the level of spending for Ukraine -- although President Joe Biden 's White House has vowed "unwavering" support for Kyiv regardless of the vote outcome.Ukraine's defence ministry meanwhile said it was requisitioning several energy and manufacturing companies of strategic importance to guarantee sufficient supplies for the military to fend off Russia's invasion.Attacks by Moscow's forces, including with Iranian-made drones over the past month, have destroyed around 40 percent of Ukraine's power stations.Kyiv has been rocked by barrages of Russian attacks on the first day of each week for nearly a month, but air raid sirens were quiet on Monday with residents out as normal.In a grey and foggy Kyiv residents were unfazed by the threat of fresh strikes Monday."To be honest, it's not only Mondays, it's been eight months that we know this can happen every day and we adapted. I'm not going to change my routine for that. I'm coming to work... just like every other day," 21-year-old Kyiv resident Alyona Plekh told AFP.Defence Minister Oleksiy Reznikov announced Monday that Ukraine had received National Advanced Surface-to-Air Missile System (NASAMS) and Italian Aspide air defences, adding to weapons supplied by Germany."These weapons will significantly strengthen the Ukrainian army and will make our skies safer," Reznikov said on social media."We will continue to shoot down the enemy targets attacking us. Thank you to our partners -- Norway, Spain and the US," Reznikov added.Meanwhile, North Korea dismissed as "groundless" claims by the United States that Pyongyang is supplying artillery ammunition to Moscow for the fighting."We once again make clear that we have never had 'arms dealings' with Russia and that we have no plan to do so in the future," the statement from the North Korean defence ministry said, according to state media KCNA.Weeks of Russian attacks have caused sweeping blackouts and restrictions on energy use across Ukraine."The situation in the power system is tense. We ask all residents of the region to support energy workers in the struggle on the energy front. To do this, use electricity sparingly," city authorities said in a statement.Those pleas come just one day after Kyiv mayor Vitali Klitschko warned of a possible total blackout in the capital.The secretary of Ukraine's national security and defence council Oleksiy Danilov said the decision to take over several companies was made "in connection with military necessity".Danilov said the enterprises include aircraft engine manufacturer Motor Sich working from the partially Russian-controlled region of Zaporizhzhia, and the oil and gas company UkrNafta.The Ukrainian presidency meanwhile said Monday that, over the last 24 hours, Russia had fired four missiles and carried out more than 24 air strikes across Ukraine.The Deputy Head of Presidency Kyrylo Tymoshenko said one person was killed by Russian shelling in the Zaporizhzhia region, and another was killed in the northeastern Sumy region.Those attacks came a day after Russian-installed authorities in the southern region of Ukraine, Kherson , said attacks by Kyiv's forces had cut power and electricity to the region's main city, also called Kherson.But authorities said Monday that power had been partially restored again in the city, towards which Ukrainian forces have been slowly advancing for weeks, saying that "all critical infrastructure" was back online.As Ukraine presses a counteroffensive in the south, Moscow's occupation forces in Kherson have vowed to turn the city into a "fortress".They have for weeks organised a civilian pull-out from the Kherson region deeper into Russian-held territory as Ukrainian troops advance, which Kyiv labels "deportations".Lyudmyla and Oleksandr Shevchuk managed to escape to Ukrainian-held territory in the Kherson region.They said Russian troops in their village of Kachkarivka put "psychological pressure" on residents to move to the Kremlin-annexed peninsula of Crimea."They would walk from house to house with their weapons. Then they would throw all the phones in a bucket and walk away," Lyudmyla said.Russia has imposed martial law and curtailed communications across Kherson and three other Ukrainian regions it proclaimed as its own, but does not fully control.