HOPES of a comeback tour by Led Zeppelin yesterday lifted shares in Sanctuary, if not to heaven, then at least to a six-month high as the band’s unexpected success in the US charts continued to bolster earnings forecasts at the music and entertainment group.

Music industry sources speculate that the success of the band’s recent US release — How the West Was Won, a triple album of live recordings — will prompt the three surviving members of the 1970s supergroup, to go back on the road on a tour that could generate upwards of $200 million (£120 million) in revenues.

Sanctuary, which manages Robert Plant, the former lead singer, and Jimmy Page, the former guitarist, receives 15 per cent of the duo’s total earnings under a longstanding contract.

But the company, which yesterday reported a 30 per cent surge in first-half turnover to £65 million, declined to comment on the speculation.

Andy Taylor, the executive chairman, said that the company was in line to record a strong second half, regardless of whether Mr Page and Mr Plant agreed to tour.

Mr Taylor said that he was “excited” at the outlook for the second half, adding that the company’s strategy of maximising revenues from all areas of music would serve as a “benchmark for the industry”.

Pre-tax profits for the six months to March 31 rose by 36 per cent to £6.4 million, against £4.7 million during the same period last year.

The company said that worldwide sales of compact discs and recorded music rose 20 per cent, “reflecting a continuing global interest in good quality music”, aided by new signings such as Ocean Colour Scene and Fun Lovin’ Criminals.

Demand for the Reggae Love Songs compilation album, which went gold in the UK within two weeks of becoming available, and has sold almost 200,000 copies worldwide, also contributed to the increase in sales.

Sales of recorded music, however, now represented less than half of the group’s revenues, Sanctuary said.

Mr Taylor said that Helter Skelter, Sanctuary’s tour management agency — the third-largest in the industry — would enjoy “one of the busiest spells in our history”, with the second half of the year looking particularly strong.

Sanctuary’s artiste management operation has added successful performers such as Macy Gray and Jane’s Addiction, and now has more than 50 artistes worldwide on its books.

Helter Skelter has already had record ticket sales from summer festivals and big tours by artistes that include Avril Lavigne, Blur, Craig David, David Gray, Eminem, Marilyn Manson, Ms Dynamite, Placebo, Red Hot Chili Peppers and Sugababes.

The company has signed a deal with BMG, part of Bertelsmann, the German media group, to develop strategic alliances in areas such as recorded music catalogues, merchandising and audio visual programming and sales.

Shares in Sanctuary closed ½p higher at 38¼p.