TORONTO/NEW YORK - ConocoPhillips (COP.N) is preparing to offload its stake in Cenovus Energy Inc (CVE.TO) that it acquired as part of an asset sale to the Canadian oil and gas producer last year, people familiar with the matter told Reuters.

The U.S. energy company has held discussions with investment banks about appointing advisors to the sale, and could offer the shares to institutional investors as early as this month, said the people. They cautioned that the precise timing would depend on market conditions and could change.

If ConocoPhillips does not complete the sale in June or early July, it would then likely wait until September when institutional investors will have returned from their summer vacations, they added.

The ConocoPhillips stake in Cenovus is worth $2.7 billion (US$2.1 billion) based on its current share price but it would likely be sold at a small discount, the sources said. It would still be one of the biggest Canadian equity share sales this year.

When Cenovus acquired oil sands and natural gas assets from ConocoPhillips for $17 billion last year, it took 208 million shares of Cenovus, as well as $14.1 billion of cash.

The deal made ConocoPhillips the biggest investor in the Calgary, Alberta-based company, although the U.S. oil giant has said it would not be a long-term holder of Cenovus equity.

ConocoPhillips and Cenovus declined to comment. Sources declined to be identified as the information is not public.