WASHINGTON – President Donald Trump says he is willing to testify to Russia special counsel Robert Mueller, but only "under certain circumstances" that continue to be subject to negotiations.

"I think it's a big waste of time because there's no collusion" with Russians who sought to influence the 2016 election by hacking Democrats, Trump told reporters aboard Air Force One en route to a political appearance in North Dakota.

Attorney Rudy Giuliani said he and Mueller's office are close to an agreement that includes written testimony, but sticking points remain.

If the parties are unable to agree on ground rules for a presidential interview, Mueller has the option of seeking to subpoena the president.

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