Ukraine and Russia: What you need to know right now

* The use of nuclear weapons is a question of global security - this is no longer just about Ukraine, presidential adviser Mikhailo Podolyak told the Swiss Blick newspaper. FIGHTING * Ukrainian President Volodymyr Zelenskiy described the military situation in eastern Ukraine's Donetsk region as difficult and said late on Monday it was the country's "No. 1 goal" because it was also Russia's No. 1 goal. * Ukraine also reported fierce fighting in Kherson in the south, where it is trying to cut off Russian occupying forces.

Europe was rushing to investigate possible sabotage behind sudden, major leaks in two Russian gas pipelines under the Baltic Sea, infrastructure at the heart of an energy crisis since Russia invaded Ukraine. GAS LEAKS

* Gas bubbles from the damaged Nord Stream 2 pipeline measure more than 100 metres in diameter, the Danish Energy Authority said. The leak will continue for several days and perhaps even a week, its head told Reuters. * Poland said the leaks were caused by sabotage linked to the situation in Ukraine, while Denmark and Russia, which slashed its gas deliveries to Europe after Western sanctions, said sabotage could not be ruled out. None of the countries said who might be behind any foul play.

* Ukrainian presidential adviser Myhailo Podolyak said the leak was "a terrorist attack planned by Russia and an act of aggression towards the EU". He did not provide any evidence in his statement on Twitter, which also called for more arms. ANNEXATION PLANS, NUCLEAR THREAT

* An ally of President Vladimir Putin issued a stark new nuclear warning to Ukraine and the West as Russia began releasing results of referendums it bills as a prelude to it annexing four Ukrainian regions. * Ukraine urged the European Union to impose economic sanctions on Russia to punish it for staging the annexation votes, which it said would not change Ukraine's actions on the battlefield, where it is staging a counteroffensive.

* Ukrainians who help Russian-backed referendums to annex large swathes of the country will face treason charges and at least five years in jail, Ukraine's presidential adviser said. * Putin is likely to announce the accession of occupied regions of Ukraine to the Russian Federation during his address to parliament on Sept. 30, the British Ministry of Defence said.

* The head of the upper house of the Russian parliament said it could consider the incorporation of the four Ukrainian regions into Russia on Oct. 4, RIA news agency reported. * The use of nuclear weapons is a question of global security - this is no longer just about Ukraine, presidential adviser Mikhailo Podolyak told the Swiss Blick newspaper.

FIGHTING * Ukrainian President Volodymyr Zelenskiy described the military situation in eastern Ukraine's Donetsk region as difficult and said late on Monday it was the country's "No. 1 goal" because it was also Russia's No. 1 goal.

* Ukraine also reported fierce fighting in Kherson in the south, where it is trying to cut off Russian occupying forces. It was not possible to verify the battlefield reports.

RUSSIAN MOBILISATION * Kazakhstan is struggling to accommodate tens of thousands of Russians who have fled their homeland since Moscow announced a military mobilisation last week, officials say, but the Almaty government has no plans to close its border.

* Thousands of Russians have also fled into Mongolia to evade conscription to Ukraine, putting further pressure on the government in Ulaanbaatar and its efforts to distance itself from the conflict. QUOTE

"Today we faced an act of sabotage, we don't know all the details of what happened, but we see clearly that it's an act of sabotage, related to the next step of escalation of the situation in Ukraine" -Polish Prime Minister Mateusz Morawiecki, referring to the Russian gas pipelines.

(This story has not been edited by Devdiscourse staff and is auto-generated from a syndicated feed.)