State Department spokeswoman Jen Psaki faced a fusillade of questions from reporters Thursday asking why the agency has yet to respond to a request for documents showing proof that President Obama's nominees for ambassadorships are qualified.

The American Foreign Service Association, the labor union for career diplomats, is unhappy with the backgrounds of several recent administration picks for ambassadorships and is now threatening to file a lawsuit.

Last summer, AFSA filed a Freedom of Information Act request for “Certificates of Demonstrated Competence” that the State Department fills out and submits to the Senate Foreign Relations Committee before nomination hearings.

It requested the certificates for every ambassador nominated from Jan. 1, 2013 to the present.

The group has yet to receive a response from State even after following up with a second FOIA request for the information on Feb. 28. The group has threatened to sue if it does not receive the information by the close of business Thursday.

Although Psaki's briefing Thursday focused mainly on the ongoing crisis in Ukraine, the department's delay in responding to AFSA's FOIA request came up.

Psaki said that State is following FOIA law and responding to information requests on a first-come, first-serve basis.

“We receive, as many of you know, about 18,000 FOIA requests per year,” Psaki said. “We generally process requests on a first-in, first-on basis. We're currently actively processing the request in accordance with the statute and the department's regulation, which applies to the specific release they put out yesterday.”

The response only prompted more questions from reporters.

“So how long should they expect to wait until you finish processing your requests, and why should they even have to submit a FOIA request for this?” one reporter asked. "Why wouldn't you just – if they asked for it – why wouldn't you just turn them over?”

Psaki declined to make a prediction on whether State would respond to AFSA's request by the close of business Thursday.

A State Department spokesman Thursday night said he didn't have an update on whether the agency had responded to AFSA's FOIA request but would keep reporters apprised of any changes.

President Obama's recent ambassadorial nominees — for Norway, Argentina and Iceland — have come under fire for flubbing basic political facts about the countries they were picked to serve.

Modern presidents have regularly tapped well-heeled campaign donors and political allies for plum ambassador assignments, but the century-long debate over whether presidents should reward big donors flared up again earlier this year. Three recent Obama nominees admitted they had never visited the countries they will serve in before being nominated.

Presidents generally follow a “70-30” rule when making the nominations, choosing career foreign service officers for the majority of posts and leaving the rest for big donors and others who helped on the campaign.

AFSA keeps a close watch on the ratio and says political allies have accounted for 37 percent of the ambassadors so far during Obama's time in office but that number rises to 53 percent if only counting those nominated in his second term.

Sen. John McCain, R-Ariz., has been particularly harsh in criticizing the caliber of Obama's nominees. In grilling Norway ambassador nominee George Tsunis earlier this year, McCain pointed out that Tsunis had a kind assessment of the country's president even though it didn't have one.

Norway is a constitutional monarchy, McCain chided. Tsunis was caught flat-footed again when he said the country's government had denounced the Progress Party. McCain tartly reminded him that the Progress Party is part of the current government.

Republicans have objected to the ambassadorial nominations, but under a Senate rule change made by Majority Leader Harry Reid, D-Nev., late last year, the so-called “nuclear option” allows nominees to win Senate approval with only a 51-vote majority. Republicans have 45 members.

The dust-up over Obama's ambassadors became fodder for late-night comedians in mid-February when “Daily Show” host Jon Stewart pointed out that three nominees had been big Obama campaign bundlers.

Tsunis had helped round-up $850,000 in support of Obama's re-election. The president's pick for Iceland had raised $1.6 million. And the Argentina nominee had directed $500,000 to Obama's re-election effort.

Henri J. Barkey, a State Department official during the Clinton administration, early last month penned a scathing op-ed in the Washington Post saying that “the Obama administration's appointments suggest that the president isn't being honest when he says that diplomacy is important to him.”