Corruption watchdog Transparency International for the first time has included Pakistan's military in an annual survey, listing it as a notch more corrupt than the country's education department.

The Pakistan chapter of Transparency International reviews and ranks government departments according to the prevalence of graft in the system.

"Our land revenue and police departments are on top in corruption. The judiciary is ranked fourth while military is in ninth position followed by the education department," Sohail Muzaffar, TI Pakistan chairman, told AFP.

Tensions between Pakistan's powerful military and weak civilian government have soared recently over alleged attempts by an aide of the president to enlist American help to curb its powers, citing a feared military coup in May.

The army, feared and admired in almost equal measure, is widely considered perhaps the most professional institution in Pakistan.

Transparency International advisor Adil Gilani said the military had been included "to dispel the impression that our surveys are biased".

"This time, we have ranked the military according to popular response about corruption in it. Next time we will have more comprehensive details," he said.

"It is public perception that others are more corrupt than the armed forces," he added.

Last year, the judiciary came in sixth.

"Delay in case proceedings and punishment has heavily contributed to the development of a perception that the judicial system has also fallen prey to corruption," said Gilani.

The Supreme Court is deciding whether to order an inquiry into the May 10 memo, a move which could build pressure on President Asif Ali Zardari, who has spent much of December fending off speculation that he could step down.