One of three groups vying for the right to operate Virginia’s port facilities for up to 50 years has removed itself from the race.

The Carlyle Group deemed withdrawal “in the interests of our partners and investors,” Carlyle Managing Director Robert Dove wrote in a letter to Ryan Pedraza, program manager for the state’s Office of Transportation Public-Private Partnerships.

The decision came after “substantial analysis and deliberation,” Dove wrote.

Carlyle and another investment group, RREEF America LLC, a unit of Deutsche Bank, lodged proposals for the port’s operation after an unsolicited bid from APM, a unit of Danish shipping giant Maersk, started the process under the state’s Public-Private Transportation Act.

Carlyle proposed a 48-year term worth an estimated $1.8 billion to $2.1 billion to the state, with the possibility of spending $1.2 billion in facility upgrades.

RREEF’s 50-year bid is worth an estimated $4.661, proposing $942 million in upgrades, while APM’s 48-year offer is estimated at $3.9 billion and would include a major expansion of APM Terminal Virginia, ownership of which would turn over to the public.

Virginia International Terminals (VIT) is also competing, for the right to continue as the operator of facilities.

The letter announcing Carlyle’s withdrawal, posted on the Port of Virginia’s website Monday, is dated Oct. 5, the day after it was the only bidder not to address a public hearing at Nauticus.

While APM and VIT both addressed that meeting at length, a speaker on behalf of RREEF said only a few words.

Authority Board of Commissioners Chairman Mike McQuillen, a VIT representative, and Secretary of Transportation Sean Connaughton were scheduled to appear Monday before the state House Appropriations Committee.

VIT transferred $819 million from port operations to the authority from 1997 to 2012, with 2011 and 2012 transfers rising above pre-recession levels, according to a presentation to the committee.

The firm says it expects to transfer, net of APMT rental costs, $13 billion to the authority over 48 years from 2013, and spend $906 million on terminal infrastructure over the next 20 years.

A presentation from Gov. Bob McDonnell’s office stated, “No decisions have been made on whether or not to enter into an agreement,” and noted that the port is one of two major East Coast ports whose cargo volumes lag behind pre-recession levels.

The deadline for detailed proposals from bidders could be pushed out to Dec. 3 for an outcome in April or May, the governor’s presentation indicated.

Responding to questions from three Virginia senators and two delegates, state Attorney General Ken Cuccinelli has issued an opinion that the VPA, as “the responsible public entity under the PPTA,” has the authority to evaluate port proposals, determine whether or not to go with one, and to approve entering into a comprehensive agreement.

The execution of an agreement would be subject to final approval by secretary Connaughton, to whom Gov. McDonnell can give “coordination and guidance” during the process, Cuccinelli decided.

Also Monday, in a public meeting on the issue at the Virginia Sports Hall of Fame in Portsmouth, the Senate Finance Committee’s Transportation and Economic Development subcommittees were scheduled to hear from representatives of VPA, VIT, the Virginia Maritime Association and Norfolk Southern Corp.