Washington, Dec 10 - US President Barack Obama unveiled his strategy for preventing the spread of biological weapons that includes increasing cooperation among countries to ensure potentially dangerous material is properly safeguarded.

The approach also calls for ensuring that adequate laws are in place to punish individuals working in or with access to biological laboratories who violate rules.

But Obama stood by the previous administration's policy of rejecting the establishment of an international mechanism to ensure that nations are complying with the 1975 Biological Weapons Convention (BWC), which bans the use and production of bio-weaponry.

The Obama and Bush administrations have argued that compliance could be ensured by promoting the BWC and calling on all nations to be more transparent in the industry. A mechanism would not be successful at detecting violations because it is too easy to disguise potentially illegal work within accepted programmes.

"We have carefully reviewed previous efforts to develop a verification protocol and have determined that a legally binding protocol would not achieve meaningful verification or greater security," US Undersecretary of State Ellen Tauscher told a conference in Geneva Wednesday.

There are 143 nations who have signed on to the BWC. (dpa)