BUZZ-Tullow Oil: Jefferies cautious about Araku
** Jefferies cuts Tullow Oil (LSE: TLW.L - news) to "underperform" from "hold", saying its 155p price target accurately reflects value of Araku exploration drilling offshore Suriname and Guyana
** Stock's closing price on Tuesday was 186.2p
** Jefferies says Araku is a "great target" with encouraging seismic data, but other parameters (target reservoir thickness, areal extent, shelf location) make it more cautious
** Jefferies also points out that co has material debt refinancing ahead of it