There are several roadblocks for any deal, however, including regulatory concerns in the United States.

Risk/benefit concerns have reached the level of international regulatory concern.

If regulatory concerns stop this deal, they could stymie future acquisitions as well.

He added that the two companies were unable to receive timely answers from governments about their regulatory concerns.

Identification of these substances in a horse is viewed with great regulatory concern.

Most recently, talks between the two sides have been hung up on regulatory concerns.

In some cases, regulatory concern makes changing a project design impossible.

But it has been delayed by regulatory and technical concerns.

The exchange initially rejected the proposal in April due to regulatory concerns.

Because of regulatory concerns within the industry, "we've got zero exposure here," he said.