Washington (CNN) Rudy Giuliani, President Donald Trump's attorney, said the President's lawyers have not heard back from special counsel Robert Mueller's office in nearly three weeks.

"I figured we wouldn't hear until after the Manafort trial, but we (still) haven't," Giuliani said.

He said Mueller's office has told them it is "still studying" the latest letter from Trump's team, which Giuliani said was only five to six pages.

"I have to figure they're planning something," Giuliani said.

He suggested Mueller's team could be considering issuing a report without talking to the President, or issuing a subpoena, which would mean the battle over a subpoena would occur during the run-up to the midterm elections. He said Muller's team may also be considering negotiating with what Trump's team offered or waiting until after the midterm elections to make its next move.

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