"The negotiations are taking place on the level of defense minister of Ukraine, we recently sent an updated list of needs to the USA… We are talking about armor and weaponry," Biryukov, who is also adviser to the Ukrainian Defense Ministry, said on the local Channel 5.
The presidential adviser said that Ukraine also is discussing the first tranche worth $350 million, with an extra billion possible.
The US side has not made the decision yet, but are not saying no, Biryukov stressed.
In recent weeks, reports emerged that Washington considered arming Ukraine, where ceasefire had been enforced Sunday. Earlier this month, US House of Representatives introduced new legislation authorizing military and lethal aid to Ukraine through 2017. However, the authorization has not been enacted by President Obama who has so far only provided Ukraine with economic and non-lethal military support.
Germany's Chancellor Angela Merkel and British Foreign Secretary Philip Hammond said their countries would not supply weapons to Ukraine in the present circumstances.
Current ceasefire in Donbas was a part of the deal hammered out by the leaders of Russia, Ukraine, France and Germany earlier this week during talks in Minsk on Ukrainian reconciliation. The agreement also stipulates withdrawal of artillery and prisoner exchanges.
