Slovenia is discussing the possibility of leasing Hungarian fighter aircraft to protect its airspace.
The small Balkan republic has light helicopters, training and transport planes, but no fighter jets of its own.
Slovenian media reported this week that the idea had been floated by Nato, which Slovenia is due to join in May.
The STA news agency said that the diplomatic and military implications of such a decision were being debated by various ministries in Ljubljana.
Leasing is a cheaper option for the Slovenian Government than buying.
Hungary's defence ministry has confirmed that talks on air defence co-operation are under way.
One official quoted by STA said the idea had been raised at bilateral meetings, but no formal requests had so far been made.
Hungarian officials have also suggested that Italy, which hosts a Nato airbase in the region, could help defend Slovenia's skies.
Hungary was one of the first countries from the former eastern bloc to join Nato in 1999.
It has 27 Soviet-made MiG 29 fighter jets and 49 Soviet-era Mi 24 attack helicopters.
The Soviet MiGs are due to be replaced with 14 leased Swedish Gripens in 2006.