Ukraine's PM tells Moscow not to wield gas as a weapon

BRUSSELS (Reuters) - Ukrainian Prime Minister Arseny Yatseniuk urged Moscow on Tuesday not to use natural gas as a new type of weapon against Ukraine.

"We are ready for a market-based approach and Russia is to stop using natural gas as another, or a new type of Russian weapon," Yatseniuk told a news conference with European Commission President Jose Manuel Barroso.

Russia's Gazprom demanded a $1.66 billion pre-payment from Ukraine for June gas deliveries on Tuesday, saying the neighbouring country had only half its requirements in storage to ensure a trouble-free winter.

(Reporting by Jan Strupczewski and Adrian Croft, Editing by Martin Santa and Robin Emmott)