And Da Costa said Villa had been turned away because Bosingwa was a player Porto wanted to keep.
The Villa boss claims he has not been in contact with Porto for the best part of a year and is looking at options elsewhere.
He told the club's official website: "We have made no bid whatsoever. It's not true.
"That doesn't mean we're not interested in players. I know this story is definitely a regurgitation because no-one from Villa has spoken to anyone from Porto in the last nine months.
"This is a categorical denial from me; it's as simple as that because we haven't spoken to anyone."