WASHINGTON — The United States on Monday defended the choice of veteran diplomat Frank Wisner to head a mission to Egypt even though he works for a firm with past work for President Hosni Mubarak's government.

Wisner was at the center of controversy Saturday when he suggested that Mubarak should stay in power during a democratic transition in the protest-hit nation. President Barack Obama's administration quickly distanced itself.

The retired diplomat has served as ambassador to Egypt, India and other nations. He has worked since 2009 for Patton Boggs, a US law firm that represented interests of Egypt and several other Arab states in the past.

Read more at ThinkProgress: US envoy to Egypt Frank Wisner’s law firm has represented the Mubarak regime in the past

State Department spokesman Philip Crowley said that the administration knew of Wisner's employment with Patton Boggs but believed he was a "distinguished diplomat" who knew Egypt.

"We felt that he was uniquely positioned to have the kind of conversation that we felt needed to be done in Egypt," Crowley told reporters.

Asked about Wisner, White House spokesman Robert Gibbs said that the State Department "selected him based on his experience with Egyptian policy."

Ed Newberry, a spokesman for Patton Boggs, said that the firm represented Egyptian interests until the mid-1990s, well before Wisner joined.

Asked about the criticism, Newberry said: "It's all based on the premise that we represent the government of Egypt, which is incorrect."

Wisner's role came under fire Monday from Robert Fisk, a veteran correspondent for the British newspaper The Independent who is often critical of US policy in the Middle East.

"Why on earth was he sent to talk to Mubarak, who is in effect a client of Mr Wisner's current employers?" wrote Fisk, who said that Wisner's actions shocked Egypt's democratic opposition and raised questions on Obama's judgment.

Despite distancing itself from Wisner's call for Mubarak to stay for now, the Obama administration has agreed that it would be difficult to organize free elections on a tight deadline and called for an "orderly transition."

A senior US official, speaking on condition of anonymity, suggested that Wisner was selected because he could deliver a "candid" message as current US diplomats may not have.

"He has a longstanding relationship with President Mubarak. We thought it was beneficial for him to be able to deliver the message," the official said.