Exactly one year after T-Mobile and Sprint announced their merger agreement, the two companies say that they're extending the deadline on their deal.

In filings with the U.S. Securities and Exchange Commission, T-Mobile and Sprint have said that they're extending the deadline for their merger to July 29, 2019. Neither T-Mo nor Sprint have offered up a statement on this decision, but the companies are still waiting for the FCC and DOJ to make a decision on whether or not the two companies should be allowed to merge.

Speaking of the DOJ, antitrust chief Makan Delrahim touched a bit on the T-Mobile-Sprint deal today. Delrahim told CNBC that he and the DOJ are still investigating the deal and that they have not decided if they'll approve the deal or block it.

“I have not made up my mind,” Delrahim said. “The investigation continues. We’ve requested some data from the companies that will be forthcoming. We don’t have a set number of meetings or a time line.”

“If the case is there for us to challenge a transaction or suggest changes, we will do that,” the DOJ antitrust head continued. “We’re all one team, the antitrust division. We will make a decision collectively. My job is to make sure that the analysis is done properly, make sure that the facts are there.”

The FCC is reviewing whether the T-Mobile-Sprint deal is in the public interest and is currently on day 147 of the 180-day shot clock on its review of the merger. Meanwhile, the DOJ is examining the merger for any possible antitrust issues.