This article is from the source 'bbc' and was first published or seen on . It will not be checked again for changes.

You can find the current article at its original source at http://news.bbc.co.uk/go/rss/-/1/hi/world/americas/6414197.stm

The article has changed 2 times. There is an RSS feed of changes available.

Version 0 Version 1
New nuclear warhead design for US New nuclear warhead design for US
(about 3 hours later)
The Bush administration has selected the design for America's first new nuclear warhead in nearly two decades.The Bush administration has selected the design for America's first new nuclear warhead in nearly two decades.
US officials say the warhead will not add to the country's nuclear arsenal, but will replace existing missiles.US officials say the warhead will not add to the country's nuclear arsenal, but will replace existing missiles.
Critics, though, argue this sends the wrong signal at a time when the White House is leading efforts to curb Iran and North Korea's nuclear ambitions. Critics have complained it sends the wrong signal at a time when the White House is leading efforts to curb Iran and North Korea's nuclear ambitions.
The chosen design was developed in a Californian laboratory and is based on a warhead already tested in the 1980s.The chosen design was developed in a Californian laboratory and is based on a warhead already tested in the 1980s.
That will satisfy the US Congress, which signed off on the idea of a new warhead on the basis that there would not be any fresh missile tests. The US Congress authorised design work on a new warhead in 2005 on the basis that there would not be any fresh missile tests.
Senior US officials, meanwhile, are stressing that this is not the start of a new arms race. No nuclear underground tests have been conducted since a ban in 1992.
They say the warheads will simply replace older, less reliable ones with a safer version that is due to be operational in five years' time. The new warhead, due to be operational in five years' time, will be used to replace Trident missiles on submarines.
But, at a moment when the White House is trying to stop North Korea and Iran from developing their nuclear programmes, some see the decision to press ahead with a new US warhead as sending an unfortunate mixed message. 'No arms race'
Making the announcement, US officials said the plan was simply to replace older, less reliable warheads with a safer version.
"This is not about starting a new nuclear arms race," said Thomas P D'Agostino, acting head of the National Nuclear Security Administration (NNSA).
Scientists at the Lawrence Livermore National Laboratory would now continue work on the design, costing and development of the programme, he said.
This could serve to encourage the very proliferation we are trying to prevent Dianne FeinsteinDemocratic Senator However, says the BBC's Jamie Coomarasamy in Washington, at a moment when the White House is trying to stop North Korea and Iran developing their nuclear programmes, some see the decision to press ahead with a new US warhead as sending an unfortunate mixed message.
Democratic Senator Dianne Feinstein was among the critics in Congress.
"The minute you begin to put more sophisticated nuclear warheads on the existing fleet, you are essentially creating a new nuclear weapon. And it's just a matter of time before other nations do the same," the Associated Press quotes her as saying.
"This could serve to encourage the very proliferation we are trying to prevent."
Nuclear non-proliferation groups have also criticised the move, warning that it could lead to proliferation and saying there is no need to replace the US' Cold War-era stockpile.
The NNSA has said the destruction of ageing warheads will mean that in five years' time, the number held by the US will be at its lowest since the 1950s.