Four US soldiers have been killed and three wounded by a roadside bomb in southern Afghanistan.
The Taleban have threatened to derail September's elections
A second bomb hit a US embassy convoy near Kabul, injuring two officials. It was not clear whether US Ambassador Ronald Neumann was in the convoy.
The Taleban claimed responsibility for both attacks although their statement could not be independently verified.
Taleban and al-Qaeda fighters have threatened to derail parliamentary elections due to be held in September.
The embassy motorcade was hit by a roadside bomb as it was travelling in the Paghman district, northwest of Kabul, on Sunday.
Paghman police chief Mohammad Nayem Ibrahimkhel said the blast was caused by a remote-controlled device.
Taleban spokesman, Mofti Latifollah Hakimi, told local media: "The Taleban detonated a roadside bomb in Paghman District... when an American embassy vehicle was passing through the area."
The other attack on US troops was in the Daychopan district of Zabul province.
The wounded soldiers were hurt while trying to pull colleagues out of their armoured vehicle.
They were later treated for shrapnel wounds at a nearby base and were said to be in stable condition.
The device had been placed under a wooden bridge and was set off by remote control as it was crossed by three 4x4 vehicles.
A US military statement said the unit "was conducting offensive operations in support of an ongoing mission to find and defeat enemy forces" at the time of the attack in Zabul province.
Earlier on Sunday, a pro-government Islamic cleric was shot dead by suspected Taleban insurgents.
Thirteen US troops have been killed in attacks on coalition forces this month and US and Afghan officials warn the violence could worsen ahead of the polls.