WASHINGTON (AP) -- Democrats and Republicans say signs of progress are emerging in urgent negotiations to avert the looming fiscal cliff ahead of a midnight deadline.

A person familiar with the negotiations says Democrats have offered to extend tax cuts for families making up to $450,000 a year and individuals making up to $400,000. President Barack Obama originally wanted the tax cuts to be extended only for families making up to $250,000 a year.

Unless an agreement is reached and approved by Congress by the start of New Year's Day, more than $500 billion in 2013 tax increases will begin to take effect and $109 billion will be carved from defense and domestic programs.

The person familiar with the talks requested anonymity in order to discuss the internal negotiations.