The attack comes just a week after Washington announced it would not be halving the 9,800 US troops still in Afghanistan by the end of the year, backpedalling on previous plans.
The Taliban, waging a deadly insurgency since they were ousted from power in late 2001, warned that the announcement would damage any prospects of peace talks as they vowed to continue fighting.
Humayoun Humayoun, a well-known MP from Khost province, was wounded in the explosion, he added in his statement.
The interior ministry in Kabul said 17 civilians were killed and 37 others were wounded in the explosion, adding that it "strongly condemns the terrorist attack".
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Protesters accusing Naeemi of rampant corruption and land grabbing have staged demonstrations outside his residence for nearly a week.
The bombs often target Afghan security forces, but they have also taken a heavy toll on civilians.
The number of civilians killed and wounded in Afghanistan jumped 22 per cent in 2014, a recent UN report said, as NATO troops withdrew from combat.
The United Nations Assistance Mission in Afghanistan attributed the rise to an intensification in ground fighting, resulting in a total of 10,548 civilian casualties last year.
A large section of Afghan society welcomed the decision, with many fearing that without continued international military support, Afghanistan -- like Iraq -- could spiral into chaos.