Global stockpiles of nuclear weapons are getting smaller, according to the latest survey of security spending by the Stockholm International Peace Research Institute (SIPRI).

The annual survey of spending in 172 countries showed that many countries were getting rid of obsolete weaponry, SIPRI said.  

But while some nations are being forced to cut their defence budgets, others are updating their nuclear capabilities. 

In Russia, military spending rose nearly 10 per cent to $71.9bn, making it the third largest military spender worldwide.

China increased its military spending by $8.2bn dollars to $143bn, an increase of six per cent over last year.

But the spending of all other powers remained dwarfed by the US, which spent $711bn - more than the rest of the top 10 combined.

Al Jazeera's Peter Sharp reports.