The 28-year-old, who has previously been linked with Sunderland, has scored eight times in 21 League One appearances this season – including a brace in October’s 5-1 win over the Black Cats.
Ladapo has been playing regularly alongside Rotherham’s top scorer Michael Smith this campaign but will be out of contract this summer – although the Millers have a 12-month option which would extend the deal until the summer of 2023.
The news was confirmed by a Rotherham club statement which said the club ‘will be making no further comment at this time.’
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Rotherham are a point ahead of Sunderland at the top of the League One table having played the same number of games.
If Ladapo does leave this month it could mean Sunderland loanee Will Grigg is handed more game time at Rotherham, although the Black Cats do have a recall clause.
Grigg has scored twice in 13 league games since joining the Millers and hasn’t started a League One match since November.
The Northern Irish striker will be out of contract at Sunderland at the end of the season and is unlikely to be handed another chance at the Stadium of Light.
When asked about Grigg’s situation in October, Warne told the Rotherham Advertiser: “Potentially they could let him go somewhere else on loan in January or they could sell him. We can’t stop that happening.
“If Griggy does really well for us and a club like, say off the top of my head, Barnsley offer £1 million in January that might be something the player and Sunderland want to do.
“That is always the disadvantage of loans: you can sometimes get a player at a good rate but you don’t have full control.”
When asked about the possibility of a recall, Warne added: “You can’t think about it until it comes. I’m solely concentrating on Rotherham and everything that is happening here. January is just something that’s in the background.”
As was the case when the sides met in October, Grigg’s loan deal would not allow him to play against Sunderland when they face Rotherham at the Stadium of Light on Saturday, March 26.