Foreign Affairs Minister Peter MacKay says he is satisfied with the co-operation of the Mexican government in the investigation of the brutal murder of a Canadian couple at a resort two weeks ago.

MacKay said he met with Mexico's Secretary for Foreign Affairs of Mexico, Luis Ernesto Derbez, last week and the Mexican government has agreed to allow more RCMP officers to participate directly in the investigation.

"This is something that we take very seriously and it is a show of good faith," MacKay told CTV's Question Period.

"We put considerable weight on the co-operation of the Mexican officials and Prime Minister Harper's involvement and that of (Mexican) President Fox demonstrate that both governments are taking the investigation extremely seriously."

Domenico and Annunziata Ianiero of Woodbridge, Ont. were found with their throats slashed on Feb. 20 in their hotel room at a resort near Cancun. They were there for their daughter's wedding.

There has been criticism that the Mexican investigation into the slayings has been badly botched as local authorities tried to protect the local tourism industry.

The Conservative government has been criticized for not putting pressure on Mexican authorities to properly investigate the murders.

Last week on Question Period, Public Security Minister Stockwell Day suggested that the government was unhappy with the conduct of the investigation.

However, MacKay denied there was a contradiction in the government's position.

"As somebody who worked with police as a Crown prosecution, these investigations always take unpredictable twists and turns. They take time. Investigative details shouldn't be discussed in public.

"... We want to ensure that the co-operation that was committed to by Secretary Durbez will be there. I have every reason to believe him. The RCMP expressed confidence in the Mexican officials and we're going to be watching extremely closely."

Friends, family pay respects

Friends and family gathered Sunday at a funeral home in Woodbridge for a second day of the visitation with the couple.

Also present were members of the York Regional Police. One investigator noted the cars and people entering.

"We have been engaged officially by the RCMP ... to assist in the interviewing of local residents who were at the gathering in Mexico at the time of the murders,'' York Const. Laurie Perks told The Canadian Press on Sunday.

"I don't have any details and will not speculate or comment on the investigation,'' Perks said. "It's an RCMP matter. We're just assisting.''

York police said they don't have a list of possible suspect yet, but that family members could be on the list.

They emphasized the Mexican authorities were leading the investigation in Mexico, and the RCMP in Canada.

The Ianieros' funeral will be held Monday morning at St. Clare of Assisi church in Woodbridge.

With files from The Canadian Press