WASHINGTON – A federal judge on Monday ordered former Trump campaign chairman Paul Manafort and his associate Rick Gates to remain under house arrest with their movements tracked by GPS devices — until they offer up more bail money to assure their future appearances in court.

Federal prosecutors, who have leveled a 12-count indictment alleging a complex money laundering and tax fraud conspiracy, said they were "close" to reaching an agreement with the men's lawyers to free them from home confinement.

But U.S. District Judge Amy Jackson said the terms their release would not be eased until bail packages for both men were approved by the court.

"We are not talking about dangerousness," Jackson said in a brief hearing Monday morning. "We're talking about (the risk of) flight."

Jackson said she was "inclined" to eventually let both Manafort and Gates out of home confinement, and was even open to allowing them to travel within the United States so they could continue their consulting work, but not overseas. "No international travel is going to be a condition of this release," she said.

Manafort and Gates were charged this month with conspiracy, money laundering and acting as unregistered foreign agents in one of the first criminal cases to come from special counsel Robert Mueller's investigation of Russian tampering in the 2016 election and its possible connection to Trump's campaign. A grand jury alleged that they worked on behalf of pro-Russia factions in Ukraine, then laundered their profits into the United States to evade taxes.

Both men have been under house arrest since they surrendered to the FBI last week.

Their lawyers have struggled to come to an agreement with prosecutors over how much money they should have to put up before they are allowed to leave their homes. Prosecutors said the effort has been complicated because the men control a tangle of bank accounts, properties and other assets, many of which are connected to charges that they moved tens of millions of dollars through overseas banks during the past decade.

Prosecutors said they have determined Manafort's net worth to be about $28 million and wanted a package worth at least $10 million to assure his future court appearances.

Jackson said Manafort had pledged three personal properties totaling $7.5 million. While the judge said the properties were "a good start, it doesn't begin to cover" the $10 million in secured assets sought by the court.

Prosecutors said they were further from reaching a bail agreement for Gates, Manafort's business associate who also worked on Trump's campaign. He had promised to put up his house in Richmond, Va., as well as unspecified assets controlled by his parents.

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In a court filing on Saturday, Manafort's lawyers said he would agree to put up $12.5 million of assets, including properties in New York and Florida and a large life insurance policy, to guarantee that he would show up at trial. They said he poses little risk of running from prosecution — in part because "there is much to question regarding the legal theories and the purported facts behind" money laundering and conspiracy charges Mueller's office outlined in the indictment last week.

Prosecutors called that offer insufficient on Sunday. They said in a court filing that Manafort had "not yet substantiated his net worth" and that the Trump Tower condo he offered to put up to secure his freedom might not be worth as much as he claimed.

"The government is not prepared to consent to a change in the current conditions of release at least until Manafort provides a full accounting of his net worth and the value of the assets that he proposes to pledge as part of his bail package," prosecutors wrote.

Last week, Manafort's lawyers Kevin Downing and Thomas Zehnle mounted their first counterattack against the federal charges, insisting in court filings that federal prosecutors had "embellished" the strength of their case. They wrote that they planned to seek “the suppression of evidence improperly obtained by search warrant, subpoena or otherwise."

FBI agents conducted an early-morning “no-knock” search of Manafort’s Virginia residence in July. Prosecutors said in an indictment unsealed last week that the search “revealed numerous documents, including documents related to lobbying."

U.S. District Judge Amy Jackson on Friday said last week she intended to schedule their trial for May 8.

Both Manafort and Gates face the prospect of long prison sentences. Prosecutors estimated in a filing that if Manafort is found guilty of all of the charges against him, federal sentencing guidelines would call for him to spend 12 to 15 years in prison.

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