(CNN) The US Office of Government Ethics has clarified that contributions to legal defense funds from anonymous donors, as well as those from lobbyists and foreign governments, are unacceptable, according to a document outlining the office's guidance obtained by CNN.

The White House had asked for advice on the use of legal defense funds, which could assist West Wing staffers who hire attorneys and sit for legal questioning -- for example, as part of investigations like Special Counsel Robert Mueller's Russia probe, as CNN reported last week.

OGE sent the document, which outlines the office's ethical recommendations on the funds, to the White House Counsel's office and also provided verbal guidance, according to a source familiar with the discussions.

Controversy over the acceptability of anonymous donations to legal defense funds arose earlier this week, when Politico reported that OGE changed a disclaimer at the top one of the agency's legal advisories. The original advisory, issued in 1993, did not require legal defense fund donors to disclose their identities.

But before leaving office, former OGE Director Walter Shaub said he added a warning to the advisory in late April or early May of 2017 that stipulated some of its language was inconsistent with OGE's current interpretation. However, on Saturday he tweeted that his warning had been removed.

"After I left, OGE appears to have quietly changed that note and thrown out two decades of practice without publicizing the change," Shaub said in a statement.

But acting OGE director David Apol disputes any suggestion that the office changed its guidance on legal defense funds.

"The policy on anonymous contributions has not changed, it is the same as when former Director Shaub left the agency," Apol said.

When asked why OGE removed Shaub's changes, Apol said Shaub's warning on the opinion regarding anonymous donors did not indicate what part of the opinion was invalid.

The note was adjusted to clarify that the much of the advisory remains valid and to encourage people to seek OGE's guidance before establishing legal defense funds, Apol said. OGE continues to recommend that funds prohibit anonymous contributions.

Apol's statement came after Politico's report Wednesday saying that OGE had quietly reversed its policy prohibiting anonymous donations to the funds from lobbyists.

Although OGE does not have enforcement authority over violations committed by legal defense funds, the office guides White House attorneys and others to help ensure the funds follow ethics laws.

A White House aide said that the White House is not helping to set up any legal defense funds and it is also not seeking to negotiate any change that allows anonymous donations.

The aide said the administration is interested in identifying ways to disclose donors and to ensure no prohibited sources contribute funds that benefit White House employees.

White House officials who have already obtained private attorneys include President Donald Trump, Vice President Mike Pence, Counsel Don McGahn, senior adviser Jared Kushner and recently appointed Communications Director Hope Hicks.