Russia said on Friday its troops were advancing in every section of the Ukrainian front, despite observers seeing little movement.

The front lines have barely shifted in 2023 but fighting has remained intense. The latest major flashpoint is the nearly encircled industrial town of Avdiivka, where Ukraine said it was fending off assaults.

"Our servicemen are acting competently and decisively, occupying a more favourable position and expanding their zones of control in all directions," Russian Defence Minister Sergei Shoigu said on Friday.

In a briefing with Russia's top military brass, Shoigu said his men were "effectively and firmly inflicting fire damage on the Ukrainian armed forces, significantly reducing their combat capabilities".

His ministry announced on Wednesday it had taken control of Khromove, a small village on the outskirts of Bakhmut in Ukraine's eastern Donetsk region, but other territorial gains have proved elusive.

Improving weather conditions -- following intense storms across southern Ukraine and Russia earlier this week -- have enabled Russia's forces to intensify their assaults and use drones again, Ukrainian officials said.

Moscow has been throwing troops and equipment at the war-battered town of Avdiivka in a bid to encircle and capture the industrial hub. 

Analysts suggest they have made incremental gains -- though at an enormous human cost -- while Ukraine said its troops were continuing to fend off Russian attacks. 

- 'Holding the line' -

"Our defenders are steadfast holding the line in the Avdiivka sector," Ukrainian army commander Oleksandr Tarnavskyi said in his daily update.

The city -- which was once home to around 30,000 people -- has been on the front line since 2014 and is part of the Donetsk region, which the Kremlin has claimed to have annexed along with three other regions.

It briefly fell to Russian-backed separatists in 2014, and Ukraine has spent the last nine years building defences and trenches to protect the city.

Tarnavskyi said Ukraine's own offensive "in the Melitopol sector" in the south was continuing.

Ukraine has struggled to claw back territory from Russia this year, despite launching a counter-offensive in June after stocking up on Western weapons.

Last month Kyiv said it had pushed Russian forces back a few kilometres (miles) from the banks of Dnipro river, which if confirmed would be its first meaningful advance in more than 12 months. 

Ahead of expectations for another tough winter, Ukraine is trying to stave off talk of fatigue among its Western partners, fearing that aid may dry up in the case of a prolonged stalemate.

Last year Russian strikes on Ukrainian energy infrastructure left millions in the cold and dark for extended periods.

- Drone attacks -

Kyiv has since bolstered its air defence systems but has conceded that it needs more weapons to protect vulnerable regions, particularly those closer to the front lines.

Russian forces launched more than two dozen Iranian-designed attack drones and two missiles on the south and east of the country overnight, Ukraine said. 

The air force said on Friday it downed 18 of the drones and one missile over southern regions.

Meanwhile Russia's defence ministry said it had destroyed a Ukrainian naval drone off the western coast of Crimea, which Moscow unilaterally annexed in 2014.

Ukraine also said on Friday it had orchestrated attacks on a Russian railway line in Siberia, thousands of kilometres from the front line, in the latest reported sabotage incident inside Russian territory.

"The Russians have fallen into the SBU's trap twice -- another fuel train has exploded on the Baikal-Amur railway," a source in Ukrainian law enforcement agencies told AFP, referring to the SBU security services.

There was no immediate public response from the Russian side but Moscow confirmed that earlier this week a train crew had spotted smoke in a fuel tank and called firefighters to the scene.

AFP was unable to verify claims made by either side.

Separately on Friday, Russia's FSB security service said it had arrested a dual Russian-Italian national for carrying out sabotage attacks under the orders of Ukrainian military intelligence.

Investigators accuse him of launching a drone attack against a military airfield in the Ryazan region in July and derailing a freight train using an explosive device last month.

bur/gil