Rural affairs expert and scholar Yu Jianrong said he has been invited for lunch and a chat at the British embassy on Tuesday, after he claimed he was treated unfairly when he applied for a UK visa.

"I've accepted an invitation from the 1st secretary from the embassy. He said they were sorry and said the ambassador [Sebastian Wood] wanted to invite me for lunch Tuesday," Yu told the Global Times Sunday.

Yu, who has been invited to a conference, went to VFS-Global, the embassy's outsourced visa application center near Chaoyangmen, Dongcheng district, to apply for his visa.

He was outraged when in addition to other documents, he was asked for a copy of his hukou (household registration). 

"I thought it unnecessary and it wasn't included in the [website's] list of required documents," said Yu. 

"I'll never provide my hukou, even if it's at the cost of not being able to attend the conference in the UK. It's my principle," said Yu.

Yu has long campaigned in China for reform of the hukou system, saying it discriminates against rural workers when they move to cities, limiting their access to schooling and other benefits.

"What made me even angrier is that when I said I would never show them the hukou, an agent standing at the next counter immediately told me that he could help me to get the visa without me providing it," Yu said.

"It's blackmail. The agent is obviously familiar with the embassy employees," he said.

According to VFS-Global's website, its agents cannot influence visa issuance, and it asks applicants to notify the British embassy if its staff claims to be able to do so. The hukou is not listed as being a requirement according to the UK Border Agency's website.

Yu said via his Sina microblog Sunday that the hukou system is designed to limit people's rights to migrate under the planned economy, and clashes with modern civilization. Requiring Chinese applicants to show this does not conform to the values the UK claims to uphold.

Liu Guofu, an expert on immigration law from Beijing Institute of Technology said an embassy can ask for any supporting documentation it likes.

"I'm not surprised a Chinese citizen was asked to provide extra documents," Liu said, "compared with the US or Japan, Chinese face more rigid requirements as China's economic and social development level is low and there are ideological differences," he said.

Staff may have asked for Yu's hukou because they did not think he was trustworthy enough, said Liu. 

"It contains information such as a person's birthplace, family members, and migration history," Liu said.

Yu is not the only one upset at UK visa regulations in China. UK business leaders called on the UK government to simplify the application process, saying it stifles trade, according to The Telegraph on January 18.

The British embassy and VFS-Global were unavailable for comment Sunday.