MOSCOW/LONDON - Qatar Investment Authority is expected to invest in the initial public offering of Russia's En+ IPO-ENG.L , sources said on Thursday, adding the flotation would be priced at the bottom of a previously announced range.

The En+ IPO is the first major float of a Russian company in London since 2014, when Moscow's annexation of Ukraine's Crimea provoked western sanctions, and one of the biggest European flotations of 2017.

QIA had bid for around $300 million of the IPO of En+, which manages tycoon Oleg Deripaska's aluminium and hydropower businesses, while U.S. Capital Group asked for around $125 million, three sources familiar with the process told Reuters.

En+ expects to raise a total of $1.5 billion through the sale of new and existing shares in London and Moscow. The proceeds will be used to pay down debt, in particular to Russian state bank VTB

QIA and Capital Group could not be reached for comment on the IPO, which is seen as a wider test of foreign investor appetite for Russian companies.

Singapore's AnAn Group, a strategic partner of China's CEFC, plans to buy $500 million of GDRs, En+ has said, while sources said Russian Direct Investment Fund (RDIF), along with a number of other investors, was also expected to invest.

One source said that the bid RDIF made along with its partners was less than $100 million. RDIF declined to comment.

QIA previously invested in Russian state oil company Rosneft ROSN.MM in a consortium with trader and miner Glencore GLEN.L . However the sovereign wealth fund cut its stake this year - a move partially blamed on a fall in the U.S. dollar against the euro, which made debt more costly.

The "books" for the IPO, which will close at 1400 GMT, were oversubscribed, one of the deal's bookrunner said on Thursday.

The listing of En+, which declined to comment, was expected to price at $14 per global depositary receipt (GDR) - the bottom of the price range of between $14 and $17 issued earlier.

JP Morgan JPM.N , Citi C.N , Credit Suisse CSGN.S , Sberbank SBER.MM , Bank of America Merrill Lynch BAC.N and VTB Capital are leading the listing. (Reporting by Anastasia Lyrchikova, Dasha Afanasieva and Olga Popova; editing by Alexander Smith) ((dasha.afanasieva@tr.com; +44)(0)(20 7542 0214;))