By Angela Quintal

Archbishop Desmond Tutu had high expectations about President Kgalema Motlanthe's caretaker role at the Union Buildings, but now counts himself among those who have been left "deeply disappointed".

This follows Motlanthe's refusal to agree to Tutu's and former president FW de Klerk's request to appoint a commission of inquiry into the arms deal.

Their campaign, spearheaded by Terry Crawford-Browne, the anti-arms deal activist, and Paul Hoffman SC, a Cape Town advocate, was supported by a host of prominent South Africans.

Motlanthe's announcement was made the day after his equally controversial decision not to reinstate Vusi Pikoli, the suspended National Prosecuting Authority (NPA) boss.

In a statement on Saturday, Tutu said he was disappointed by the president's response.

"I thought we were in a new dispensation. If there is nothing to hide, a commission should be set up that satisfies everybody. It is no good referring to an in-house investigation."

Tutu said there could be no smoke without a fire, given all the "suspicions" about arms deal corruption, including investigations by authorities in Britain, Sweden, the United States and other countries, as well as the Organisation for Economic Co-operation and Development.

In a letter dated December 12, Motlanthe said he had "most carefully considered" Tutu and De Klerk's request contained in an open letter.

Their grounds for an inquiry was based on the "reasonable apprehension that allegations of impropriety and corruption" in the arms deal had substance.

"You have mentioned issues such as law-enforcement raids on premises, detentions for questioning, alleged bribery and laundering of money, and the active involvement of various authorities locally and abroad in the cause of dealing with what are clearly suspected criminal activities," the president said.

He noted that after the 2001 multi-agency probe into the deal, the National Prosecuting Authority was tasked with follow up investigations, which was currently the case.

The appointment of a commission would therefore amount to a parallel investigation and would not "at this stage assist in bringing about greater clarity or resolution of the issues at stake", the president said.

The "ordinary process of the law" should be sufficient to get to the bottom of any well-based allegations against anyone, "at whatever level inside or outside government", he said.

"But," Tutu said, "since neither the NPA nor the Specialised Crime Unit has taken seriously the request for investigation lodged by Richard Young on March 26 2008 and the criminal complaint lodged by myself on August 20 2008, the suggestion that evidence of corruption should be lodged with the police is both gratuitous and spurious."

He added: "Corruption and abuses of human rights are invariably intertwined.

"People are rioting all over South Africa to protest the government's failure to meet socioeconomic expectations.

"Given the international financial crisis and its consequences for South Africa, it is again unfortunate that the government still refuses to meet its constitutional obligations of transparent and accountable public administration."