Updated: 2:34 p.m.

The ongoing feud between the top Republican and Democrat on the House Oversight and Government Reform Committee flared up again Monday — this time over the exclusion of government witnesses from an upcoming hearing on the federal government’s role in Bank of America’s acquisition of Merrill Lynch.

The Oversight panel has been investigating why the merger between Bank of America and Merrill Lynch was first announced as a stock-only transaction.

Tuesday’s hearing will be the fourth held by the committee since the beginning of this year. Four Bank of America board members are expected to testify.

Oversight ranking member Darrell Issa (R-Calif.) wrote in a letter to Chairman Edolphus Towns’ (D-N.Y.) on Monday that his failure to call government witnesses to testify at this week’s hearing suggested that Towns isn’t taking the investigation seriously.

“I do not believe a serious investigation into the Merrill Lynch acquisition can be conducted without questioning these officers,— Issa wrote to Towns. “By failing to call government witnesses to this hearing, the Committee is abdicating its responsibility to oversee the government policies and actions that shaped the Merrill Lynch acquisition.—

Issa said that as of last week he and his staff had been assured that Federal Deposit Insurance Corp. Chairwoman Sheila Bair, former Securities and Exchange Commission Chairman Christopher Cox and current SEC Chairwoman Mary Schapiro would appear before the committee. Issa accused Towns’ staff of acting in “bad faith— by telling Republican members that the current and former government officials would testify at the hearing when in fact they were not scheduled to do so.

“As disappointed as I am that the Committee is not taking the steps necessary to conduct a serious investigation and to oversee government policy and actions, I am equally disappointed that the actions of your staff — deliberately or not — misled the Republican Members of the Committee,— Issa said.

Jenny Thalheimer Rosenberg, a spokeswoman for Towns, said Issa’s allegations were “baseless,— noting that Federal Reserve Chairman Ben Bernanke and former Treasury Secretary Henry Paulson appeared before the committee this summer to testify about the merger.

“This hearing is about the Bank of America Board members,— she wrote in an e-mail. “We call witnesses based on the evidence we receive, not who we want to attack politically.—

But Issa spokesman Kurt Bardella said the original witness list for the hearing, first scheduled for Oct. 22 but later postponed, included Bair, Cox and Schapiro.

“Why was it pertinent to have government witnesses just a few weeks ago, but now it’s somehow labeled partisan gamesmanship?— Bardella asked. “All we’re asking for is a little consistency, but it’s clear that they have forgotten they invited them to participate in the hearing in the first place.—

Asked about the original witness list, Rosenberg confirmed that the three officials had been scheduled for the Oct. 22 hearing.

“Depending on what happens tomorrow, if the Chairman determines the committee needs information from them in the future, I’m sure he will reach out to them,— Rosenberg said.

The back and forth between Issa and Towns over the testimony is just the latest in a series of spats for the Members. The disagreement began earlier this year when Issa began pursuing an investigation into a controversial mortgage program by failed lending giant Countrywide for public officials and other prominent figures. And just last month, Towns infuriated Issa when he locked GOP members out of an Oversight meeting room.