3i Group PLC (London: III) the largest-listed U.K. private equity company, is in talks with Spain's Ferrovial to sell its Enterprise maintenance and cleaning company, the Financial Times reported.

Ferrovial is expanding its foreign holdings and already owns U.K. support company Amey, which maintains roads, airports and parks in Britain.

Enterprise has been a problematic investment for 3i, which wrote down its entire 200 million pound ($323 million) equity stake in the company in 2011 due to debt problems. Enterprise, whose clients include the Westminster city council, has suffered from contracted public spending in the public sector in the wake of the 2008 financial crisis.

3i's stock has fallen by around 25 percent in the last year as it has warned of smaller earnings in its holdings. CEO Michael Queen said he would resign in March after 25 years at the company.

The company's stock was down 3.11 percent to 188.75 pounds ($305.62) at Monday's close.