The Stockholm International Peace Research Institute says China increased its arsenal of nuclear warheads from 240 to 250 last year as part of efforts to modernize its military.

The Swedish think tank said Monday that China apparently is focusing on enhancing the quality of its nuclear weapons rather than increasing its supply.

The institute added that India and Pakistan also increased their arsenals by around ten warheads each in the past year.

The U.S. and Russia, meanwhile, reduced the number of their warheads in line with the new Strategic Arms Reduction Treaty they signed in 2010. The U.S. cut its arsenal from eight-thousand to 77-hundred and Russia reduced its arsenal from ten-thousand to 85-hundred.

Nevertheless, the institute said that the U.S., Russia, France, China and Britain have either deployed new nuclear weapon delivery systems or unveiled plans to do so.

A researcher at the institute, Shannon Kile, said “there is little to inspire hope that the nuclear weapon-possessing states are genuinely willing to give up their nuclear arsenals.”