Shares in British oil firms extended gains on Wednesday after the government announced changes to the tax system in the sector to provide relief for the industry in the face of a slump in crude oil prices.
UK finance minister George Osborne said he would effectively abolish the petroleum revenue tax, while reducing the rate of a "supplementary charge" on oil and gas producers.
Shares in Cairn Energy (CRNZF), John Wood Group and Tullow Oil (TUWLF) extended gains after the measures were announced, and were up 2.7-3.6 percent.
(Reporting by Alistair Smout)