Google has agreed to delay the start of a Web advertising partnership with Yahoo to give U.S. antitrust regulators more time to review the deal.

Two weeks ago, Google CEO Eric Schmidt told The Associated Press he would not wait much beyond the intended Oct. 11 start date.

But in a statement Friday, the Mountain View, Calif.-based company said that since it was still in talks with the Department of Justice, it has agreed to “a brief delay” in implementing the agreement while the discussions continue.

On Thursday, The chairman of the Senate Antitrust Subcommittee asked the Department of Justice to scrutinize Yahoo’s plan to outsource some search ads to Google and to monitor the deal if it goes forward.

“We conclude that important competition issues are raised by this transaction,” Sen. Herbert Kohl (D-Wis.) wrote Thursday in a letter to assistant attorney general Thomas Barnett.

But Kohl stopped short of calling for the DOJ to block the deal or impose conditions on it. Instead, he asked officials to keep an eye on the situation in the future. “Even should you conclude at present that this deal is not contrary to antitrust law, the Department must be sure that this deal never in the future crosses the line into an unacceptable, anti-competitive collaboration among competitors which will harm consumers and advertisers.”