LONDON—Britain's defense secretary says thousands of troops are being told if they will lose their jobs amid the country's austerity measures.

Philip Hammond said Tuesday that about 4,100 military staff would be lost as the defense ministry conducts a second round of job cuts.

Britain has announced that it will cut a total of 17,000 troops and 25,000 civilian staff. It means the country's army will number about 82,000 by 2015.

A fleet of jets, an aging aircraft carrier and 40 nuclear warheads are also being lost amid an 8 percent cut to the military's annual 37 billion pound ($58 billion) defense budget over four years.

Prime Minister David Cameron is driving through a four-year program of about 81 billion pounds ($126 billion) of cuts to government spending.