Hyatt Hotels Corporation stepped back from making a bid for NH Hotel Group, saying an offer now looks impractical. The Spanish operator's shares are at their lowest.

Hyatt wrote to NH Hotel Group’s board about a possible bid proposal on July 26. Two hours later, Minor International disclosed that it controlled 44 percent of the Spanish company’s shares.

Also read: Hyatt Hotels: 11th largest hotel supply in the world?

"Based on the information we now have, we believe that the path to a successful tender offer by Hyatt under the terms expressed in our letter has narrowed to a point of being impractical," said Mark Hoplamazian, President and Chief Executive Officer, in a letter dated July 29 that was disclosed to Spanish regulators by NH Hotel Group.

"Hyatt miscalculated the whole thing," said Dilip Rajakarier, Chief Operating Officer of Minor International, by phone on July 30.

Also read: Minor International: “Hyatt has entered the church and the bride has already left”

NH Hotel Group fell as much as 7.1 percent in Madrid, the biggest drop since February 6. The shares were down about 6 percent to 6.35 euros at 1:20 P.M, giving the company a market value of about 2.5 billion euros ($2.9 billion).

Minor International’s offer for the portion of NH Hotel it didn’t own was valued at 1.64 billion euros ($1.92 billion) in early June, when the plans were first announced.

If NH Hotel "wishes to open a dialogue with Hyatt to pursue other potential paths to unlock value for NH shareholders, we stand ready to do so," said Hyatt Hotels Corporation.