Russia is reinforcing its occupation of Ukrainian regions under its control by sending a senior official to a war-ravaged city and forcing residents to use Russian passports.

The Kremlin sent Deputy Prime Minister Marat Khusnullin, who is in charge of urban development and construction, to Mariupol in Eastern Ukraine. Video clips of him visiting construction sites were shown on Friday.

Pro-Russian groups there say that he will be involved in rebuilding infrastructure.

Russia is also speeding up efforts to force residents in the territories it has occupied to use Russian passports.

US think tank the Institute for the Study of War says that people are now required to show Russian passports when they obtain mobile phones in the southern region of Kherson and the southeastern region of Zaporizhzhia.

The think tank says that the Kremlin wants to urge residents to get Russian passports and monitor those who are against Russian control.

Meanwhile, Russian forces continue attacking eastern and southern parts of Ukraine.

Russia's defense ministry announced on Saturday that missile attacks on a Ukrainian troop position in the eastern region of Dnipropetrovsk killed more than 80 people.

It also said its forces shelled the eastern region of Donetsk and the southern region of Kherson.

It said it targeted Ukrainian positions.

Governor of the Donetsk region Pavlo Kyrylenko wrote on social media on Saturday that five people died and 14 others were injured.