Nasdaq Chief Executive Robert Greifeld said on Wednesday the unvarying response from OMX shareholders has been that they prefer its bid to a rival higher cash bid from Borse Dubai.

It's very straightforward. It is the uniform response that Nasdaq's bid is the preferred alternative, Greifeld told a news conference.

We have not heard anybody say that the industrial commercial logic is not compelling, he said.

The U.S. exchange group has bid $3.7 billion in cash and shares for OMX, which runs exchanges in Sweden, Denmark, Finland, Iceland and the Baltic states.

Nasdaq is competing against a rival cash bid of $4 billion from Borse Dubai.

Greifeld said he believed OMX and Nasdaq together would be in a unique position to compete for market liquidity but said OMX investors were also looking at the difference in face value of the rivaling bids.

Obviously they want the two numbers to be closer, he said.

Greifeld declined to offer more details on whether Nasdaq would sweeten its offer, which currently values OMX shares at about 207 crowns, compared with 230 crowns for the Borse Dubai bid, but reiterated that the U.S. group would be flexible in the final structure of its offer.

We think there is a time and a place for us to do a final consideration of our bid, but we are not at that time and place yet.