(Adds Rufino comments on tariff increases and transmission debts)
By Leonardo Goy
BRASILIA, Feb 26 (Reuters) - The head of Brazil's electricity regulator, Romeu Rufino, told Reuters on Friday he favors allowing troubled Spanish multinational Abengoa SA to sell its power concessions in the country but does not rule out taking them back if the company cannot find a buyer.
Rufino, who has headed the regulator, known as Aneel, since 2013, said the government would give buyers a new timeframe to deliver the transmission lines that had been under construction by Abengoa.
Brazilian media reported earlier this month that the government was considering intervening in the indebted energy company after it failed to pay 375 million reais ($93.76 million) it owed to investment bank Grupo BTG Pactual SA.
Abengoa, which is on the brink of becoming Spain's largest ever bankruptcy, does not even have enough cash to pay wages in February, its chairman told employees on Friday.
In Brazil, Abengoa operates seven transmission lines and is building nine others, including one that will link the massive 11,233-megawatt Belo Monte hydroelectric dam in the lower Amazon state of Para with the national grid.
Abengoa's gross corporate debt was around 9 billion euros ($9.9 billion) in November, but it swells to about 25 billion euros when project financing and what it owes to suppliers is included.
Rufino said that the annual readjustments of electricity tariffs should be smaller than inflation in 2016, limited to a single digit hike. Inflation climbed to 10.67 percent in 2015, its highest in more than 12 years.
The government has said electricity bills could actually drop during the year as authorities turn off expensive gas-consuming thermal plants after heavy rains boosted hydroelectric output.
Lower tariffs will help a central bank struggling to slash inflation that has remained high despite a crippling recession.
Rufino said he estimates that the government owes about 28 billion reais to power transmission companies stemming from the early renewal of their contracts in 2012.
The cash-strapped administration has delayed those payments, prompting many companies to threaten to halt investment until they are repaid. ($1 = 3.9995 Brazilian reais) (Reporting by Leonardo Goy; Writing by Alonso Soto; Editing by Bernard Orr and Cynthia Osterman)