On the same day Moscow celebrated its historic victory over Nazi Germany, Russian forces continued their assault on parts of Ukraine.

But new intelligence from the UK is highlighting Russia's failures on the ground.

Reports say a Russian missile attack on the southern port city of Odesa killed one person and wounded five others on Monday. Officials said seven missiles hit a shopping mall and a warehouse.

Odesa Mayor Gennadiy Trukhanov said, "We are at a facility that was hit by a Russian missile. This facility had nothing to do with military infrastructure or military objects."

The President of the European Council and Ukraine's Prime Minister were in the city for talks. In a social media post, Denys Shmyhal said they evacuated to a bomb shelter together.

The Russian defense ministry says pro-Moscow militants have expanded areas under their control. They say they've reached the administrative border of the Luhansk region.

Further south, an official in the city of Mariupol says at least 100 civilians remain inside the steel plant where Ukrainian troops are holed up. They said the Russians continue to attack the plant. Another official is warning that Russia could use a chemical weapon there.

But new intelligence from the British defense ministry says Russia underestimated the Ukrainian resistance and that has led to operational failings. It says the Russians mistakenly assumed they would be able to achieve a rapid victory with minimal cost.

The ministry says that prevented President Vladimir Putin from announcing significant military success in Ukraine at Monday's Victory Day parade.

Meanwhile, the United States has enacted a law to provide military aid to Ukraine more quickly. It revives a World War Two era program.

President Joe Biden said, "I'm signing a bill that provides another important tool in our efforts to support the government of Ukraine and the Ukrainian people in their fight to defend their country and their democracy against Putin's brutal war and it is brutal."

A senior Pentagon official says almost all 90 howitzers the US is handing over are already in Ukraine.