Labor has asked the auditor general to investigate the government’s claimed $7bn in drought assistance, saying the response has been “ad hoc, confusing and lacking in direction”.

As the government defends the roll-out of its drought package, which saw one regional council receive $1m in taxpayer support despite enjoying good rainfall, Labor’s shadow agriculture minister, Joel Fitzgibbon, has written to the auditor general, Grant Hehir, requesting a full audit.

He said an inquiry into all drought funding initiatives since 2014 was needed to ensure they had been “both effective in assisting farmers and rural communities and are delivering value for taxpayers”.

The request also asks Hehir to look at the criteria underpinning the Drought Communities Program which has excluded some local government areas “that were clearly more drought-affected than some that were included”. This is in reference to the Moyne council in south-west Victoria which is expected to reject the $1m grant.

“As large parts of Australia suffer the worst drought on record, the government’s response has been ad hoc, confusing and lacking in direction,” Fitzgibbon said on Tuesday.

“Farmers and rural communities are tiring of prime ministerial drought tours, empty talk about dams, exaggerated funding announcements and now, what appears to be political favouritism and pork barrelling.”

The government has been under pressure over its drought assistance measures since minister David Littleproud told parliament that the government would not release reports written by the special envoy on the drought, Barnaby Joyce, nor a report prepared by the government’s drought coordinator, Major General Stephen Day.

Despite Littleproud saying no report existed in relation to Joyce’s work, the former Nationals leader has said he sent an “awful lot” of correspondence relating to his role, including 1,500-word text messages.

On Tuesday, Joyce hit back at critics of his role, including Fitzgibbon, accusing the shadow agriculture minister of neglecting to visit drought-affected communities.

“I think it is only fair enough that Mr Fitzgibbon answer – where is his trip to Dubbo? Where is his trip to Longreach? Where is his trip to Charters Towers?

“The only trips I can see all bar one are near the coast – these are the the seats that the Labor party were trying to win at the election.”

Fitzgibbon has questioned what value taxpayers received from the Joyce appointment, which cost taxpayers $675,000 over a nine-month period, including Joyce’s normal activities as a backbencher, but excluding his salary and that of two extra staff assigned to the role.