The Stockholm International Peace Research Institute (SIPRI) released its annual yearbook of analysis on developments in armaments, disarmament and international security on Monday.
In the report, SIPRI says that while the total number of nuclear weapons in the word has declined, nations that possess nuclear weapons are opting for more sophisticated versions of the weapons that are left and are showing no signs of complete disarmament.
Between the five countries legally recognized to possess nuclear weapons - China, France, Russia, the United Kingdom and the United States - there were a total of around 19,000 nuclear weapons worldwide at the start of this year. Of those, 2,000 are kept in a state of high operational alert. This is down from 20,530 at the beginning of last year.
Despite the downward trend, countries with nuclear weapons have either already developed new nuclear weapon delivery systems or are in the process of doing so. SIPRI says these countries appear to want to hold on to their nuclear arsenals indefinitely.
"In spite of the world's revived interest in disarmament efforts, none of the nuclear weapon-possessing states shows more than a rhetorical willingness to give up their nuclear arsenals just yet," said SIPRI Senior Researcher Shannon Kile in a statement on the group's website.
"While the overall number of nuclear warheads may be decreasing, the long-term modernization programs under way in these states suggest that nuclear weapons are still a currency of international status and power."