The US dropped more bombs on Afghanistan in 2019 than any other year since the Pentagon began keeping a tally in 2006, reflecting an apparent effort to force concessions from the Taliban at the negotiating table.

According to new figures released by US central command, US warplanes dropped 7,423 bombs and other munitions on Afghanistan, a nearly eightfold increase from 2015.

The increasing intensity of the air campaign has been accompanied by an increase in civilian casualties attributed to US forces. According to UN data, the US accounted for half the 1,149 civilian deaths attributed to pro-government forces in Afghanistan over the first three-quarters of 2019.

The Taliban and other insurgent groups were responsible for 1,207 civilian deaths, according to the same figures, as the Taliban also stepped up its attacks over the summer. In July last year, the UN recorded the highest number of civilian casualties in a single month since the organisation began documenting civilian casualties in Afghanistan in 2009.

The surge in bloodshed came as the US and Taliban were conducting sustained peace talks, which were led on the US side by the special envoy Zalmay Khalilzad. Donald Trump abruptly called off the talks in September, blaming a Taliban suicide attack in Kabul, which killed an America soldier. The president claimed that Taliban leaders were on the point of coming to Camp David to sign an agreement, a claim the Taliban denied.

After making his first visit to Afghanistan in November, Trump declared he had reopened talks with the rebel group.

Male relatives comfort 12-year-old Bilal as he breaks down in tears in a Jalalabad Hospital bed beside his uncle Zarghun Shah, left, two days after they survived a US drone strike that killed their father and brother respectively. Photograph: Andrew Quilty/The Guardian

“This is the US military mistakenly thinking that they’re somehow going to change the political dynamics by dropping more ordnance on Afghanistan,” said Laurel Miller, former US acting special representative for Afghanistan and Pakistan, who is now director of the International Crisis Group’s Asia programme.

“The argument that is made in favor what they’re doing is that this will somehow change the political dynamics and in a way that makes the Taliban more likely to come to favorable terms at the peace table, but I have no expectation that this is going to have that kind of effect,” Miller said.

“It also poses the considerable risk of of blowback in the sense that inevitably this increase in use of air power results in an increase in civilian casualties.”

After the Obama administration tightened the criteria for carrying out aerial attacks, there was a significant decrease in bombing in 2015, but at the same time, the Taliban made territorial gains, leading to calls in Washington for the rules to be loosened again. Trump relaxed the criteria, giving more authority to commanders in the region to call in airstrikes, contributing to the surge in bombing.

“The US side is very explicitly hoping to use the ramped-up strikes to gain leverage in the ongoing talks with the Taliban,” said Frances Brown, who served as a senior national security council official in both the Obama and Trump administrations, and is now a fellow at the Carnegie Endowment for International Peace.

“The Taliban side is also using their own ramped-up violence to gain leverage; as a consequence, we saw record levels of overall violence in the third quarter of 2019, as both sides thought they were heading toward a preliminary agreement,” Brown said.

“The problem here is that the Trump administration lacks the clear political negotiating strategy,” she added. “The US special envoy made some hard-fought progress over the course of 2019, only to have the rug yanked out from under him by the president, with no apparent rationale. The talks restarted a few weeks ago, but the US has now undermined its own hand.”