By Matthew Collin
BBC News, Qabala, Azerbaijan
The new role would require a big revamp at Qabala
Standing beneath the dramatic Caucasus mountain range in northern Azerbaijan, the Qabala radar station is a stark concrete block which dominates the rural landscape.
This former Soviet installation is now at the centre of discussions between Moscow and Washington.
Russian President Vladimir Putin suggested it could be used for a joint missile defence project as an alternative to the United States' plan to build a missile shield in Europe to guard against attacks from what it describes as "rogue states". The US sees Iran - bordering on Azerbaijan - as a potential threat.
Qabala is an integral part of Russia's defence system, leased from the Azeri government and used since the 1980s for monitoring missile launches, with an estimated range of 6,000 kilometres (3,720 miles).
It provides work for hundreds of Azeris, as well as the many Russians who are based here. It remains top-secret, and is protected by checkpoints and electrified fences.
Some people in nearby villages were wary of discussing the radar station openly. But others expressed fears that it was emitting harmful radiation.
"This station is very dangerous, it badly affects people's health," Sabir, a retired farmer, told the BBC.
"Plants are dying, vegetables do not grow, and lots of women and children have health problems."
There was also scepticism about any possible US involvement in the radar station, which once tracked American military activity.
"I do not think the Americans will bring anything good here," said Mustafa, a local teacher. "They haven't ever done anything for Azerbaijan and they only act in their own interests."
President Putin's proposal came as a surprise in Azerbaijan, as it did in the West. But Azerbaijan's President Ilham Aliyev responded positively, saying it would serve the country's "long-term strategic interests".
Azerbaijan is an oil-rich former Soviet republic which has grown in importance since it began supplying energy to Western markets through new trans-Caucasus pipelines.
President Bush has described Mr Putin's idea as 'interesting", and it will be discussed when the two leaders meet in July.
But the Russian military analyst Alexander Goltz suspects that Mr Putin's offer was simply a political ploy to upset US plans, and questions whether using the Azeri installation would be technically viable.
"If you take this seriously, Qabala at least needs to be modernised because it has a totally different purpose at the moment. It cannot guide interceptor missiles," Mr Goltz told the BBC.
"The question is whether the US will agree to use Qabala to show it has a close partnership with Russia. It's about political strategy, not military strategy."
Concerns have also been raised that the proposed missile defence project could damage Azerbaijan's relations with neighbouring Iran. The US believes Iran is trying to develop nuclear weapons.
An Iranian foreign ministry spokesman has warned that US involvement at Qabala could cause "instability and insecurity" in the region.