Russian authorities say Ukraine has launched an "unprecedented attack" on and around St Petersburg, as the city hosts the final day of Russia's annual economic forum.

More than 140 drones were shot down over the surrounding Leningrad region, governor Aleksandr Drozdenko said, while the city's governor, Alexander Beglov, urged residents to remain indoors for the first time since the war began more than four years ago.

Ukraine's president said his forces had hit Russia's arsenals and a naval base in what he called a just response to Russian attacks.

It comes a day after Vladimir Putin told the forum there was no point in meeting Volodymyr Zelensky, who had called for direct talks on ending the war.

The commander of one of the Ukrainian units involved in the drone strikes told the BBC that it was very easy to hit targets inside Russia.

"We fly in Russia like it's our own territory. Almost no resistance, not hard to reach a target," Yevhen Karas, commander of the 413th regiment Raid of Ukraine's Unmanned Systems Forces, said.

Governor Drozdenko said Ukraine's attacks had caused a fire at an unspecified military facility, and that residents had been evacuated. He also said buildings had sustained "insignificant" damage.Zelensky said his country's drones had covered a distance of 1,000km (620 miles) to the St Petersburg region, targeting "the enemy navy's arsenals and a base in Kronstadt". The main outpost of the Russian Navy's Baltic Fleet is located in Kronstadt.

According to Zelensky, an oil depot 500km (310 miles) away, in the southern Krasnodar region, was also hit as part of Ukraine's "long-range sanctions" - a euphemism for strikes on Russia.

The Ukrainian president said it was "time to end this war", but accused Russia's leader of wanting to "keep fighting".

These latest attacks follow Ukrainian strikes on the outskirts of St Petersburg as Putin's flagship economic forum was getting under way just days earlier.

The major forum, designed to attract foreign investment into the country, drew thousands of guests from 130 countries, including a low-key US delegation - the first for many years.

In his open letter to Putin on Thursday, Zelensky called for a ceasefire and face-to-face negotiations with the Russian leader to end the war, which began with Russia's full-scale invasion in 2022.

He wrote that it would be "wrong to simply wait" for the conflict to once again come to the attention of the US. President Donald Trump has been involved in efforts to mediate an end to the conflict, but the war with Iran has recently taken precedence.

Speaking at the economic forum on Friday, Putin refused the request for a meeting with Zelensky and reiterated his position that a truce would only allow Ukraine to regroup.

He said he would only end the war when Russia's goals had been met.

Russia's long-standing position is that Ukraine should withdraw from the Donetsk, Luhansk, Kherson and Zaporizhzhia regions it has largely seized, as well as abandon efforts to join Nato.

Ukraine has refused to give up any territory, arguing that concessions to Moscow would embolden it to invade again in the future.

In the Russian-occupied Luhansk region of eastern Ukraine, the Moscow-installed authorities say they have suspended coach services on two motorways following a campaign of Ukrainian drone strikes targeting Russian logistics.

They urged local residents not to use them "for security reasons".

The Russia-backed administration also banned commuter train services and transportation of groups of children within Luhansk.

Putin has said Russia is in full control of the so-called "Luhansk People's Republic".

In recent weeks, Ukraine's drone forces have been hitting occupied parts of Ukraine, with officials saying they are targeting Russian logistics.

An analyst told the BBC that more than 200 lorries and over 30 fuel trucks had been hit since the beginning of May.

In the four years since Russia's invasion began, Ukraine has developed its defence sector.

Kyiv is now able to regularly hit targets within Russia. It has focused its efforts on energy infrastructure and oil facilities, which it sees as fuelling Moscow's war machine.

Russia has accused Kyiv of targeting civilians. (BBC)

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