WASHINGTON — Government-controlled mortgage buyer Freddie Mac is asking for $1.8 billion in additional federal aid after posting a larger loss in the second quarter.

Freddie Mac said today it lost $6 billion, or $1.85 per share, in the April-to-June period.

The company is required to pay a 10 percent annual dividend to the Treasury Department on money it has received from the government. That made up $1.3 billion of the company's second-quarter losses.

The company lost $840 million, or 26 cents a share, in the same quarter last year.

The government rescued McLean, Va.-based Freddie Mac and sibling company Fannie Mae from the brink of failure nearly two years ago. The new request means they have needed $148.2 billion to stay afloat, about $63.1 billion of which is being used by Freddie Mac.

Freddie Mac is losing money from bad loans it backed, many of them before the housing market went bust. It had $118 billion in bad loans at the end of June, up from $103.4 billion at the end of last year.

Both Fannie Mae and Freddie Mac have both lost tens of billions of dollars during the past two years and both are asking the government to prop them up.