April 4 (Reuters) - ** Shares of oil companies fell in premarket trading following prices of crude

** Brent futures LCOc1 fall 3.5% to $67.69/bbl; U.S. West Texas Intermediate crude futures CLc1 decline 3.8% to $64.43/bbl by 0926 GMT - both on course for their biggest weekly losses in percentage terms for half a year

** Crude weighed down by hit from U.S. President Donald Trump's barrage of new tariffs and output increases announced by the OPEC+ producer group O/R

** U.S. oil majors Exxon Mobil XOM.N down 1.7%, while Chevron CVX.N falls 1.5%

** Producers Occidental Petroleum OXY.N down 1.4%, Permian Resources PR.N slips 1.7%, while oilfield services company Halliburton HAL.N declines 2.6% and top oilfield co SLB SLB.N down 1.2%

** Europe's oil cos .SXEP down ~3%, with BP BP.L slipping 2.1% and Shell SHEL.L falling 2.6%

(Reporting by Seher Dareen in Bengaluru)

((Seher.Dareen@thomsonreuters.com; If in India call +91 74832 70128;))