RUSSIA was poised today to formally annex parts of Ukraine where occupied areas held a Kremlin-orchestrated “referendum” — denounced by Kyiv as illegal and rigged — on living under Moscow’s rule.

Armed troops had gone door-to-door with election officials to collect ballots in five days of voting. The results were widely ridiculed as implausible and characterised as a land grab by an increasingly cornered Russian leadership following embarrassing military losses in Ukraine.

Moscow-installed administrations in the four regions of southern and eastern Ukraine claimed Tuesday night that residents had voted to join Russia.

“Forcing people in these territories to fill out some papers at the barrel of a gun is yet another Russian crime in the course of its aggression against Ukraine,” Ukraine’s Foreign Ministry said, adding that the balloting was “a propaganda show” and “null and worthless.”

Pro-Russia officials in Ukraine's Donetsk, Kherson, Luhansk and Zaporizhzhia regions said today that they would ask Russian President Vladimir Putin to incorporate their provinces into Russia.

According to Russia-installed election officials, 93 per cent of the ballots cast in the Zaporizhzhia region supported annexation, as did 87 per cent in the Kherson region, 98 per cent in the Luhansk region and 99 per cent in Donetsk.

Meanwhile, the EU expressed outrage over the suspected sabotage of two underwater fossil gas pipelines from Russia to Germany on Tuesday.

European Union foreign policy chief Josep Borrel said “all available information indicates those leaks are the result of a deliberate act,” even though the perpetrators haven’t so far been identified.

“Any deliberate disruption of European energy infrastructure is utterly unacceptable and will be met with a robust and united response,” he said.

Kremlin spokesman Dmitry Peskov said allegations that Russia could be behind the incidents were “predictable and stupid,” saying the damage has caused Russia huge economic losses.

In February, US President Joe Biden told reporters that "if Russia invades [Ukraine]... then there will be no longer a Nord Stream 2. We will bring an end to it."

When a reporter asked how the US would do that since the project is under German control, President Biden said: "I promise you, we'll be able to do it."