Ulster Unionist leader Doug Beattie has said it was "clear" that a meeting he had with Sir Jeffrey Donaldson last year was to discuss the DUP MP potentially switching parties.
Mr Beattie said he has texts of exchanges with Sir Jeffrey and signalled he may publish the messages if his integrity is challenged.
Sir Jeffrey, who later became DUP leader, has denied reports that he considered rejoining the UUP after he lost out in a leadership battle to Edwin Poots.
