Afghan authorities imposed a partial lockdown on the capital Thursday, banning trucks from the city's streets in a bid to prevent suicide bombings ahead of presidential elections on Saturday.

The election is at high risk of violence and the Taliban have already unleashed a slew of suicide attacks across Afghanistan targeting campaign offices, rallies and other election-related targets.

A truck bombing in Kabul on September 5 killed at least 12 people.

The interior ministry said in a statement that security forces were beefing up their presence at checkpoints into the city and would turn trucks back.

"The Afghan police forces are manning the entry gates, and are ordered to prevent the entry of trucks into Kabul from today 5:00 pm (1230 GMT)," the statement read.

"Also, the entry of mini-trucks is banned in the city until the end of the elections."

The move comes the same day as the Taliban issued a statement reiterating previous threats that anyone voting was at risk.

The Taliban "intend to disrupt this fake process of the American invaders and their few servile slaves by attacking all security personnel... and by targeting (polling) offices and centers," the insurgents said.

They went on to warn Afghans "to stay away from polling stations on election day and not throw themselves into danger".

Truck bombs are a constant danger in Afghanistan and carry an explosive yield far greater than a car bomb.

In May 2017, a massive truck bomb exploded near the German embassy, killing more than 150 people and wounding hundreds more.

Pakistan, where many Taliban fighters come from, announced Thursday that it was tightening security along the Afghanistan-Pakistan border during the elections.