Source of tens of millions of dollars of donations hidden, according to analysis of AEC data, with government under pressure to reform electoral laws. Almost $70m of “dark money” flowed to the major parties and the Greens in the past financial year, a Guardian Australia analysis reveals, as the Albanese government pushes to pass laws to overhaul the opaque political donations regime. The Australian Electoral Commission (AEC) published the latest annual figures on political donations on Monday, providing a glimpse into the big money sloshing around federal politics.

Labor’s branches received a total of $67.5m in receipts in the past financial year, compared with the Liberals’ and Nationals’ combined $72.2m. The Greens received $17.1m. However, the source of tens of millions of dollars’ worth of donations remains hidden due to disclosure rules that allow donations under $16,300 to slip under the radar. A Guardian Australian analysis of the AEC figures revealed that of the $156m in receipts from Labor, the Coalition and Greens, the source for $67.2m was not declared.

Sign up for Guardian Australia’s breaking news email. The Liberal party had the highest proportion of what transparency advocates describe as “dark money”, with half of its receipts not declared. The federal government’s proposed reforms would lower the disclosure threshold to $1,000, bringing far greater transparency to the donations. The chief executive of Transparency International Australia, Clancy Moore, said the scale of “dark money” highlighted the need for change.

“We urgently need the parliament to pass laws to introduce real-time disclosure of donations, lower the donation disclosure threshold to $1,000 and close the MCG-sized loophole to the definition of ‘gift’ that allows millions in ‘dark money’ to line the pockets of the major parties,” he said. Labor is yet to clinch a deal to pass its electoral laws ahead of a scheduled debate in the Senate on Thursday.

The new regime would cap individual donations at $20,000 and limit spending to $800,000 per electorate, or $90m nationally during a federal election. Anthony Albanese has indicated the government was open to split the legislation to get it through the Senate, with Labor sources adamant the government is willing to deal with either the Coalition or the Greens and the crossbench. However, crossbench sources believe Labor wants to strike a deal with the Coalition that would potentially disadvantage minor parties and independents.

Crossbenchers Kate Chaney and David Pocock held talks with the special minister of state, Don Farrell, on Monday to push the case for the legislation to be carved up. Under their proposal, the caps would be referred to an inquiry while the remainder of the bill would pass. The caps are designed to restrict billionaires such as Clive Palmer, who pumped almost $120m into his United Australia party ahead of the 2022 election.

The mining magnate was conspicuously absent from the latest AEC figures after topping the list in recent years. Share trader Rob Keldoulis and his investment firm Keldoulis Investments were revealed as the biggest single donor in 2023-24, pumping $1.1m into the Climate 200 fundraising vehicle that backs community independents. The Visy chairman, Anthony Pratt, was the second-biggest donor, handing $1m to Labor.

Climate and energy market-focused trader Marcus Catsaras rounded out the top three, donating just under $1m to Climate 200. The rightwing advocacy group Advance tripled its receipts last financial year to $15.6m, from the $5.2m in donations it raised the year prior. The group has pledged to “expose” the Greens as Australia’s “biggest threat to freedom, security and prosperity” in the upcoming election campaign.

Advance’s largest single contribution came from the Cormack Foundation, best known as an investment company for the Liberal party, at $500,000. The newly released figures showed wagering companies also donated tens of thousands of dollars to Labor as the government mulled reforming sports betting before ultimately shelving any legislation. Sportsbet donated $88,000, Tabcorp $60,500 and peak body Responsible Wagering Australia gave $66,000.

The two major parties continue to receive donations from fossil fuel companies. Gina Rinehart’s Hancock Prospecting donated $500,000 to the Coalition, while the Minerals Council of Australia gave $382,465 in donations to several Labor and Coalition branches. The Greens senator Larissa Waters said the proposed electoral reforms were urgently needed to “reduce the influence of big money in politics”.