* Deputy secretary of state warns of pressure to arm rebels
* Easy for Moscow to send arms into Ukraine, Blinken says
* U.S., Europe fear they could be dragged into proxy war (Updates with more quotes and original English transcript)
By Stephen Brown
BERLIN, March 6 (Reuters) - The second-highest ranking U.S. diplomat warned on Friday that pressure to arm Ukraine would increase if aggression from pro-Russian separatists persisted, even though Moscow would easily be able to send more weapons into the country than the West.
Deputy Secretary of State Antony Blinken told German radio (DLF) the United States was already working on supplying Kiev with non-lethal equipment, including $130 million worth of protective vests, night-vision goggles and other equipment.
"But if the aggression continues, I think there will be more and more pressure to give them other means to protect themselves," he said in the interview with DLF.
With both the government in Kiev and the rebels in eastern Ukraine accusing each other of violating a fragile ceasefire agreed last month, U.S. President Barack Obama and European leaders are weighing their next steps to try to halt a conflict that has killed about 6,000 people since last April.
U.S. and European officials are concerned that sending arms to Kiev would risk escalating the fighting and suck them into a proxy war with Russia.
But some U.S. lawmakers are urging Obama to counter what they see as increased aggression by Russia by providing weapons to Kiev.
Blinken said he did not believe there could be a military solution and the emphasis must be on diplomatic efforts, which continued on Friday when European Union foreign ministers met in Latvia and Berlin hosted separate talks among top foreign ministry officials from Ukraine, Russia, France and Germany.
"And you know, it's certainly true that, were any of us to provide weapons to Ukraine, Russia could match that and then double that and triple that and quadruple that," he told DLF.
"But it's also important to have in mind that the Ukrainians should be able to defend themselves and we provided significant security assistance, defensive, non-lethal security assistance to Ukraine to do just that," he said.
Accusing the separatists "who are armed and supplied by the Russians" of repeatedly breaking ceasefires declared by Ukraine throughout the conflict, Blinken added: "At some point you have to say almost as a moral proposition, we have to do whatever we can to help them defend themselves against aggression."
Moscow denies Western and Ukrainian accusations that it is backing the rebels in eastern Ukraine with troops and weapons. (Editing by Gareth Jones)
Our Standards: The Thomson Reuters Trust Principles.