Xerox (XRX) - Get Report sent a letter to HP Inc.'s (HPQ) - Get Report board asking the printer and computer maker to open up its books in order to move the negotiating process forward following its proposed $32.6 billion, $22-per-share takeover bid, which HP rejected earlier this week.

HP is about three times the size of Xerox and the company pointed out that Xerox's business is in decline . HP also noted that such a merger between the two companies would involve a lot of debt. 

"We were very surprised that HP's Board of Directors summarily rejected our compelling proposal to acquire HP for $22.00 per share ... claiming our offer 'significantly undervalues' HP. Frankly, we are confused by this reasoning in that your own financial advisor, Goldman Sachs & Co., set a $14 price target with a 'sell' rating for HP's stock after you announced your restructuring plan on October 3, 2019," said Xerox's letter to HP.

Xerox added that its offer represents a 57% premium to Goldman Sach's price target and a 29% premium to HP's 30-day weighted average trading price of $17 per share. 

Part of HP's rejection, however, also featured some of the merits of a combined company, a fact Xerox acknowledged in its letter. 

"While we are glad to see that HP's Board of Directors acknowledges the substantial merits of a business combination between Xerox and HP and are open to exploring the value opportunity for our respective shareholders, your response lacks a clear path forward," Xerox wrote in the letter.

Bloomberg has reported that HP would actually like to purchase Xerox, as opposed to the other way around. 

Xerox closed its letter out by threatening a hostile takeover attempt if HP does not agree "on mutual confirmatory due diligence to support a friendly combination."

Xerox shares rose 0.81% to $38.61 on Thursday, while HP shares were down slightly to $19.70.