NATO Secretary General Anders Fogh Rasmussen speaking in Brussels Friday urged the Western alliance and Russia to consider linking their defensive missile systems. (Virginia Mayo/Associated Press)

The cancellation of a long-planned missile shield for Eastern Europe by the United States set off a flurry of reaction Friday in Europe.

NATO Secretary General Anders Fogh Rasmussen urged the Western alliance and Russia to consider linking their defensive missile systems to combat the proliferation of such technology in other countries.

"If North Korea stays nuclear and if Iran becomes nuclear, some of their neighbours might feel compelled to follow their example," Rasmussen said in Brussels.

In Sochi, Russian Prime Minister Vladimir Putin praised U.S. President Barack Obama's decision to scrap plans for a missile defence system in Europe, hailing the move as "right and brave."

He also urged the U.S. to cancel trade restrictions on Russia.

Meanwhile, Turkey's military said it will spend $1 billion US on four long-range missile defence systems.

Turkish Foreign Minister Ahmet Davutoglu denied media reports that Turkey is buying missile interceptors against Iran.

On Thursday, Obama said he is shelving a plan that would have put a missile defence system in the Czech Republic and Poland. The Bush-era project had been opposed by Russia.

Instead, the U.S. will launch a new program in 2011 that will focus on sea- and land-based missile interceptors. The system is also set to include a range of sensors in Europe to defend against ballistic missile threats from the Middle East.

The move came about because of a change in the U.S. perception of the threat posed by Iran.