Russia has no plans to sell Syria an advanced air defense system, its foreign minister said on Friday, denying media reports that it planned such a sale.The Wall Street Journal reported on Wednesday that Israel had informed the United States a Russian deal is imminent to sell advanced ground-to-air missiles that would significantly boost Syria's ability to stave off intervention in the conflict. The newspaper quoted US officials as saying they were analyzing the information, but would not comment on whether they believed the sale of S-300 missile batteries was near.Itar-Tass news agency quoted Foreign Minister Sergei Lavrov as saying Russia would be fulfilling contracts it has already concluded with Damascus but that this did not include sales of the S-300 system.On Thursday, US Secretary of State John Kerry said the United States does not want Russia to sell weapons to Syria and has opposed transfers of missile systems to the country in the past because of the threat to Israel."I think we have made it crystal clear we would prefer that Russia was not supplying assistance," Kerry said at a news conference after meeting Italian Foreign Minister Emma Bonino.Pressed about the report, Kerry suggested he may have raised the issue with Russian President Vladimir Putin and Foreign Minister Sergey Lavrov, whom he met in Moscow on Tuesday.After those meetings, the two countries agreed to seek new peace talks to end the conflict."I had my say with President Putin and I had my say with Sergey Lavrov and we made an agreement to go to a negotiation in the next days and I am not going to get into here, now, at this moment, as I said, distinguishing features between one country's aid and another country's aid and who's doing what," he said."That would be counterproductive to what we are trying to accomplish," he added.The White House also sidestepped the issue."We are aware of the reports. But I have no further information for you on it. We have consistently called on Russia to cut off the Assad regime's supply of Russian weapons, including air defense systems that are destabilizing to the region," White House spokesman Jay Carney told reporters aboard Air Force One as US President Barack Obama headed to Texas.The government of Syrian President Bashar Assad has been seeking to purchase the advanced S-300 missile batteries, which can intercept both manned aircraft and guided missiles, from Moscow for many years.Western nations have repeatedly urged Russia to block the sale, which they argue could complicate any international intervention in Syria's escalating civil war.The Journal said the information provided to Washington by Israel showed that Syria has been making payments on a 2010 agreement with Moscow to buy four batteries for $900 million, including a payment made this year through Russia's foreign-development bank, known as the VEB.The paper said the package included six launchers and 144 operational missiles, each with a range of 125 miles (200 miles), with an initial shipment expected in the next three months.While the effectiveness of Syria's aging air force is unclear, most experts believe that its air-defense missile system, which was upgraded after a 2007 Israeli strike on a suspected nuclear site, remains quite potent.