OTTAWA -- Former employees of now defunct Canadian International Development Agency might need as long as a decade to get used to the idea they have been subsumed by the larger foreign ministry.

That is a key finding of an internal government report on the 2013 decision by the former Conservative government to merge CIDA with the larger Department of Foreign Affairs and International Trade, as it was then known.

Consultant Alain Jolicoeur wrote in a report delivered to the government last year that it could take five to 10 years for CIDA employees to accept the "cultural change" associated with the merger.

The Canadian Press obtained a copy of Jolicoeur's report under access to information.

The demise of CIDA, a stand-alone agency created in the late 1960s to oversee foreign aid and international development, caught virtually everyone off guard when the Conservatives announced it in a single paragraph of the 2013 federal budget.

The current Liberal government -- which renamed the foreign ministry Global Affairs Canada -- is carrying on with the merged department and is nearing the end of a major review of how the country delivers international development.

Critics have said that merging foreign policy, trade and development under one roof would give short shrift to fighting poverty, but the Conservatives and the Liberals both say having all three under the same roof will lead to a more coherent international agenda.

Peter Boehm, the deputy minister in charge of development at Global Affairs, said it has been easier to respond to the new Liberal government's foreign affairs agenda by having people together in the amalgamated structure.

But as Jolicoeur's report makes clear, this idea did not go down well with rank and file CIDA employees when it was announced in 2013.

"It came as a big surprise (shock and awe) to basically everybody, even though the concept had been discussed for years," he wrote in the 28-page report that included interviews with more than two dozen senior department managers, ambassadors and former officials.

Government managers moved quickly to make the amalgamation happen, holding town hall meetings with employees and "focusing on the strengths that each side had to offer," the report said.

The initial three phases of the amalgamation progressed well as common systems and structures to keep the department running were put in place, it said.

"The fourth phase will involve the more difficult cultural change and will easily take five to ten years until a critical mass of employees ... operate in the new mode automatically."

The report said CIDA employees were initially "very concerned about their future" and didn't see it as an amalgamation because "DFAIT was significantly larger than CIDA and spoke with a bigger voice."

The report also estimated that two years into the process about 90- to 95-per cent of the amalgamation had been completed, but reiterated that "on the cultural side" it could take another five to 10 years.

"Personnel need to change, new reflexes need to appear, and innovation needs to take place. We are clearly not at this point."

Boehm said the concept of "bureaucratic cultural change is not an alien thing," noting the department went through the same when the former Industry, Trade and Commerce department joined External Affairs, as it was then called, in the early 1980s.

"It took a while for that to really sink in and for the change to come into effect," he said in an interview.

Boehm said the government consulted with European countries that had undergone similar amalgamations.

"We discovered that they were saying that the cultural change was almost a generation," added Boehm, who was also interviewed for the report. "So I think for Alain to say four to five years, that's entirely reasonable."

Conservative MP Deepak Obhrai, who was parliamentary secretary for development at the time of the merger announcement, said his government was well aware that cultural differences would have to be overcome.

"But I don't agree with the fact that it's going to take that long," he said in an interview.

"We've got excellent officers working out there who are well aware that this is necessary," he added. "They know that change has taken place."