Hungarian Prime Minister Viktor Orbán has signed a decree allowing NATO troops to move through and be stationed in the country.
Orbán approved the move on Monday in the wake of Russia's invasion of neighbouring Ukraine.
But he also banned the shipment of weapons and lethal equipment to Kyiv.
Non-lethal aid — such as personal protective equipment, medical supplies and humanitarian materials — is still permitted to cross the Hungarian border to Ukraine.
The government decree reaffirmed Orbán's earlier insistence that Hungary would only allow NATO forces to transit across Hungary into other NATO member countries.
Orbán — a nationalist leader — has not asked NATO to help defend Hungary's border, unlike other countries.
Hungary's foreign minister Péter Szijjártó had previously told Euronews that Budapest would not accept additional NATO troops on its soil.
"The Hungarian armed forces [...] are in proper shape to guarantee the security of the country," Szijjártó said last month before Russia launched its assault on Ukraine.