A memo at the heart of allegations that International Co-operation Minister Bev Oda breached parliamentary privilege was edited by an aide and stamped with an automatic signature, the Conservative government says.

Background documents sent to members of the Conservative caucus assert the memo was not doctored, but prepared while Oda was out of Ottawa on business.

The internal memo, obtained by CTV News, comes after several days of allegations that Oda altered the documents and then misled Parliament about a decision not to fund the foreign aid agency KAIROS.

While opposition parties have been calling for Oda to resign, Tory MPs have come to her defence, saying she had the final say on whether to cut funding.

Oda has admitted that she had someone alter a Canadian International Development Agency document by adding the word "not" to it, negating the recommendation of funding for the group after it had been signed by officials.

"Everyone in the House of Commons knows Bev Oda has the final say with respect to CIDA and who is approved and who is not approved," Conservative MP Dean Del Mastro told CTV's Question Period on Sunday.

Oda did not answer questions about the controversy in the House of Commons this week. Prime Minister Stephen Harper and House Speaker John Baird responded in stead, ostensibly sidestepping questions about how the document came to be doctored.

In the background information obtained on Sunday, the government refers to the process of editing internal documents as a common practice to convey a minister's decision.

"The Minister has been clear: this was her decision," the leaked document states.

The memo says Oda decided the request was inconsistent with the government's foreign aid priorities.

KAIROS, a church-based organization with decades of experience in foreign aid service, made a request for CIDA funding in the amount of $7 million.

CIDA officials sent the memo in question to Oda, seeking a decision on whether to approve the funds. CIDA officials had approved the funding, but Oda did not agree, according to the background notes.

Because Oda was travelling outside of Ottawa the day her staff finished the paperwork, an aide applied her automatic signature and changed the document to read that she did "not" approve the funding application.

The explanation is unlikely to satisfy critics, who have questioned assertions that Oda had the final say on cutting the funding to KAIROS.

"We see the government in full damage control. We have a minister that won't stand up and say what she did and be accountable," NDP MP Paul Dewar told CTV's Question Period.

"Who knows what the story is anymore. She has undermined her credibility to the point where no one believes her. But the question is who directed her on this decision?"

Meanwhile, the opposition tabled a motion last week asking for House Speaker Peter Milliken to rule on whether Oda breached parliamentary privilege.