A potential MEP was among 21 people killed in a devastating suicide attack in Afghanistan.
Dhamender Singh Phangurha was due to stand as a Labour candidate in the South East region, which includes Sussex, at the European elections in May.
This morning confirmed he was one of two British nationals killed in the blast in Kabul.
Party colleagues took to social media sites to pay tribute to the politician and international development worker, who was known as Del.
Warren Morgan, Labour group leader on Brighton and Hove City Council, said: "Awful news about Labour South East European Parliamentary candidate Del D Singh - so sad for his family and all who knew him."
Purna Sen, Labour's candidate for Brighton Pavilion, said: "Such horrible, tragic news.It's a loss to us all. Thoughts are with his family."
The blast occurred at the Taverna du Liban restaurant, which is popular with tourists and westerners, in the Afghan capital, officials say.
The FCO has confirmed that two British nationals are among those killed in the incident.
A spokeswoman said: "We can confirm the deaths of two British nationals in Afghanistan on the 17th of January."
The suicide attacker detonated his explosives outside the gate of the heavily fortified restaurant, the deputy interior minister Mohammad Ayoub Salangi said.
Two gunmen entered the restaurant and started shooting at people inside. It is believed they were eventually shot dead by security forces when they arrived at the scene.
The restaurant is in an area home to several embassies, non-governmental organisations and the homes and offices of Afghan officials, and like most places frequented by foreign diplomats, aid workers, journalists and businessmen in the war-weary country, has no signs indicating its location and is heavily secured.
It is on a small side street in the diplomatic quarter of the central Wazir Akbar Khan area, just off a bumpy semi-paved road in a house with low ceilings and an enclosed patio, but no windows.