Stockholm, Jun 7 (AFP) More than 5,000 nuclear weapons are deployed around the world and nuclear powers continue investing in new weapon systems, making meaningful disarmament in the near future unlikely, a report published today said.

"More than 5,000 nuclear weapons are deployed and ready for use, including nearly 2,000 that are kept in a high state of alert," according to a report by the Stockholm International Peace Research Institute (SIPRI).

SIPRI's report said the world's eight nuclear powers -- Britain, China, France, India, Israel, Pakistan, Russia and the US -- possess more than 20,500 warheads.

As of January 2011, Russia had 11,000 nuclear warheads, including 2,427 deployed, while the United States had 8,500 including 2,150 deployed, the report said.

The US and Russia have signed a Strategic Arms Reduction Treaty (START) that calls for a maximum of 1,550 warheads deployed per country.