The Times is reporting that the US is expected to provide cluster munitions to Ukraine. These controversial munitions have already been used in the war on both sides especially by Russia- most notably in the Kramatorsk train station attack. Neither Russia or Ukraine, or the US for that matter, are party to the treaty that bans their use.
They would help Ukraine attack Russia's fortified trenches. Each bomb ejects many tinier bomblets over a wide area. But they are known to have a failure rate of unexploded ordinance that could endanger civilians. Of course much of Ukraine is covered in mines and explosives already from the Russian occupation.