Blake Shelton and ex-wife Miranda Lambert are still ''buddies.''

The country music stars shocked fans when their divorce was finalised in July just hours after they confirmed their split after four years of marriage, and the 'Voice' USA mentor admits it happened ''so fast'' because they had a prenuptial agreement in place and don't have any children.

The 39-year-old singer said: ''In Oklahoma, it happens so fast. Like, Miranda and I didn't have any kids, and we had a prenuptial agreement, whatever we had. Once we filed for divorce, it was over in, like, I think it was like a nine or 10-day waiting period until it's over.

''We knew if rumblings and rumours started coming out, they would just be that. By the time anybody knew anything, it was over... It was done.''

While the decision appeared to have been sudden, the 'Sangria' hitmaker and the blonde beauty, 31, exchanged friendly messages on Twitter a few days later sparking rumours a reconciliation was in the works at the time.

But Blake told the 'Bobby Bones Show': ''Our whole thing was, we are going to be cool about this, it is what it is. We're buddies.''