Some 18,000 guns with ammunition have been distributed to reservists in the Kyiv region alone since the Russian invasion began early Thursday, according to Ukrainian authorities, CNN reported.
In a joint statement, defence minister Oleksiy Reznikov and Valeriy Zaluzhniy, chief of staff for the Armed Forces, said there were more arms coming.
"Soon we are to receive additional support with modern weapons and other resources from our partners," they said, CNN reported.
On Thursday, Ukrainian President Volodymyr Zelensky ordered a general military mobilisation.
Zelensky said that "in order to ensure the defence of the state, maintaining combat and mobilisation readiness of the Armed Forces of Ukraine and other military formations", a broad-based mobilisation was ordered, including in the capital, Kiev, and all Ukraine's major cities.
This included a ban on all male citizens from 18- to 60-years-old leaving the country, according to the State Border Guard Service, CNN reported.
The mobilisation also instructed the "conscription of conscripts, reservists for military service, their delivery to military units and institutions of the Armed Forces of Ukraine" and other state security services.