Fantastic. This is a significant development. Poland will send a company of Leopard 2 main battle tanks. The UK is sending the Challenger 2 MBT. Hopefully this will encourage other countries to finally start sending heavy tanks to Ukraine as the fighting gets more entrenched.
This follows the US, France, and Germany sending some infantry fighting vehicles to Ukraine last week. The US sent Bradley fighting vehicles. France sent AMX-10s. Germany sent Marder fighting vehicles.
Previously the tanks sent to Ukraine were older Soviet-era tanks from stockpiles.