LONDON (REUTERS) - Hong Kong pro-democracy activist Nathan Law said on Wednesday (July 15) he feels safe in London at the moment but described the extra-territorial reach of national security laws imposed by China as "scary" and urged Britain to do more to help.

Law, a former legislator, left Hong Kong earlier this month after China imposed a new national security law on the territory that has been heavily criticised by the West.

He said he had agreed with fellow senior activists to come to London, where allies and a large Diaspora would help keep an international voice for their protest against Beijing.

"I feel relatively safe here," Law told British lawmakers in a webinar, describing how he had previously kept his location secret after receiving threats.

The British flag was lowered over Hong Kong when the colony was handed back to China in 1997 after more than 150 years of British rule - imposed after Britain defeated China in the First Opium War.

Britain says the national security law breaches agreements made before the handover and that China is crushing the freedoms that have helped make Hong Kong one of the world's biggest financial hubs.

Hong Kong and Beijing officials have said the law is vital to plug holes in national security defences exposed by the protests. China has repeatedly told Western powers to stop meddling in Hong Kong's affairs.

Asked about the reach of the new security laws in Hong Kong, Law said it covered foreigners and their actions outside Hong Kong: "That is scary," he added.

He urged Britain to follow other countries and review its extradition arrangements with its former colony.

Law also said he wanted Britain to consider extending its offer of a route to citizenship, which already applies to nearly three million Hong Kong citizens, to include something for younger people, especially pro-democracy demonstrators.

"We really welcome and appreciate the measures and we could still explore and look into more development on that in order to send a stronger signal," he said.