MADRID, Oct 18 (Reuters) - Spanish banks' bad loans as a percentage of total lending rose slightly to 12.1 percent in August from 12 percent in July, marking a new high, Bank of Spain data showed on Friday.

The ratio has been steadily climbing in recent months as households and small companies struggle with debts, although at some banks bad debts grew more slowly in the second quarter.

Spain's economy is set to emerge from a two-year recession by the end of this year, although many analysts and bankers forecast that bad loans will peak in early 2014.

Bad debts rose by just over 2 billion euros ($2.7 billion)to 180.7 billion euros in August, the data showed.