The death toll from a huge car bomb attack in Afghanistan's capital Kabul on Tuesday has more than doubled, according to the government. 

An interior ministry spokesman, Sediq Sediqqi, said on Wednesday that most of those killed by the blast, which hit a security agency office in the heart of the city, were civilians.

"It is with regret that I announce that 64 people were killed and 347 others wounded in yesterday's Kabul attack," Sediqqi said. 

The assault, which was claimed by the Taliban, was the group's first major attack in Kabul since it announced the beginning of its annual spring offensive. 

In a statement, the Presidential Palace condemned the attack "in the strongest possible terms".

ANALYSIS: The Taliban's resurgence in Afghanistan

Al Jazeera's Qais Azimy, reporting from Kabul, said the attack was probably the biggest such incident to hit the capital since 2001.

The Taliban had warned that they would "employ large-scale attacks on enemy positions across the country" during the offensive - dubbed Operation Omari in honour of the movement's late founder Mullah Omar.

The government in Kabul has been trying to bring the group back to the negotiating table in a bid to end the country's drawn-out conflict

A recent resurgence by the group has raised questions about the ability of Afghan forces to hold their once NATO forces withdraw from the country.

Source: Agencies