By Koustav Samanta and Scott DiSavino
NEW YORK (Reuters) - Oil prices climbed to their highest in five weeks on Thursday, as buoyant Chinese equity markets encouraged buying, and as Russia's military involvement in Syria brought a geopolitcal risk premium into the market.
The market shrugged off concern about the higher-than-expected U.S. crude stock build as reported by the U.S. Energy Information Administration on Wednesday.
Brent crude oil futures rose $1.60 to $52.93 a barrel by 1:07 p.m. EDT (1707 GMT), after touching a five-week intra-day high of $53.30. U.S. crude futures rose $1.46 to $49.27 a barrel.
PIRA Energy Group, a closely watched forecaster that predicted the collapse in oil prices a year ago, said it sees crude prices at $70 per barrel by the end of 2016 and $75 a barrel in 2017.
Chinese stock markets rose 3 percent after a week-long holiday, the biggest rise in two trading weeks.
"Sentiment regarding China appears to have shifted of late and we feel that further stability in the Chinese stock market will limit downside price follow-through across the energy complex," said Jim Ritterbusch, president of Galena, Illinois-based Ritterbusch & Associates.
Syrian troops and allied militia backed by Russian air strikes and cruise missiles attacked rebel forces as the government extended a major offensive in the west.
The United States ruled out military cooperation with Moscow and called its strategy "tragically flawed."
"The situation is getting complicated very quickly and raising the geopolitical risk in the region to a new high," Energy Management Institute analyst Dominick Chirichella said about the ongoing conflict in Syria.
"This has caught the attention of the market place (and) is viewed as a situation that could potentially impact the flow of oil from the region as well as degrading the already declining relationship between Russia and the U.S."
Brent is on track to rise more than 10 percent this week, close to its largest weekly increase since early 2009, after oil industry executives warned that this year's fall below $50 would force higher-cost producers to reduce output.
"There was a hiccup with the U.S. data this week, but production is still expected to continue to slow," Saxo Bank commodities strategist Ole Hansen said.
Underpinning the crude complex was a drop in the dollar ahead of the release of the minutes of the Federal Reserve's most recent policy meeting.
A weaker dollar tends to make it cheaper for non-U.S. investors to buy dollar-denominated assets.
(Addtional reporting by Amanda Cooper in London, Aaron Sheldrick in Tokyo; Editing by David Gregorio)