British oil company BP (BP.L) has decided to keep its U.S. wind farm business, one of the largest in the country, after four months in which it failed to attract a bid the company could accept, a spokesman said on Tuesday.

"We didn't find an offer that we thought was the right value," said the spokesman, citing guidance circulated by management at the end of last week.

"Our feeling is that the business is more valuable to us than to others. We had a number of bids, but we decided now is not the right time to sell."

The sale was seen as a continuation of the retreat of big oil companies from renewable energy investments while oil and gas projects offer them better returns.

It would also have helped fund BP's oil spill costs along with the $38 billion worth of assets it has already sold since the 2010 spill.

Bp has not put a value on the business but reports have said the sale could have raised a further $1.5 billion.

The assets include interests in 16 operating wind farms in nine states with a combined generating capacity of around 2,600 megawatts, as well as a portfolio of projects in various stages of development.

BP reported second quarter results earlier on Tuesday.