Di son of Hong Kong media tycoon Jimmy Lai don call im imprisonment by Chinese authorities as "death sentence".

Di 78-year-old British citizen bin dey sentenced on Monday for 20 years. Dis na afta dem find am guilty of national security offences last December. Dis go be di harshest sentence wey dem don eva give under di city controversial National Security Law (NSL).

Lai na one of di loudest critics of China, as e dey normally use im pro-democracy paper, Apple Daily, take protest. E don always deny di charges against am.

Sabastian Lai tell di BBC say e believe say dem dey punish im papa becos im dey "defend di freedom of Hong Kong".

As British citizen, Sebastian tell di BBC Radio 4 Today programme, say Lai deserve more.

Sebastien tok say, "as man wey don give so much for liberty, for freedom, im deserve small for imsef".

Di Foreign Secretary Yvette Cooper don tok say di UK govment wan "rapidly engage more" wit Beijing so dem go fit free Lai.

Cooper tok for statement say, "I again dey all on di Hong Kong authorities to end dis yama-yama happening and to release am for humanitarian grounds, so e fit dey united wit im family."

She add say, "we dey stand wit di pipo of Hong Kong".

Lai na pesin wey dey hailed as hero for di pro-demcracy movement but Beijing see am as traitor.

Westerm govment wey including UK and US don dey call for im release for years but Beijing and Hong Kong neva gree.

China bin introduce di controversial National Security Law for 2020 to ansa pro-democracy protests wey bin rise for Hong Kong for di year bifor.

Di law make wider range of dissenting acts to dey illegal. Dis acts include anytin wey di state see as secession, subversion, terrorism and collusion wit foreign forces.

E also allow Hong Kong to send cases go Mainland China for trial.

Dem find Lai guilty of foreign collusion and publishing seditious material for under di NSL.

Court find say im use im now closed Apple Daily newspaper as part of wider effort to take ginger foreign govments to impose sanctions for Hong Kong and China.

Dem don hold am for solitary confinement for one maximum security prison for di last five years. Dis na situation wey im son don tok say don make im health suffer well-well.

Im pikin tok say, "Becos of im health, becos of im heart issues, becos in di last year alone im don lose pass 10kg, dat na basically death sentence".

For trip to Beijing last month, Prime Minister Keir Starmer tell tori pipo say e bin bring up di mata of Lai release.

Sir Starmer tok afta im meeting afta President Xi Jinping, say, "part of di reasoning for engagement na to make sure say we fit both seize opportunities wey dey ground, and na wetin we don do, but also to get mature tok-tok on matas wey we no gree for".

Afta dat visit, di UK govment bin announce say Beijing don gree to allow UK citizens to travel visa-free for trips wey no go reach 30 days.

Di trip also make dem cut import taxes on UK whisky from 10% to 5% as govment wan dey close to Beijing on trade to ginger di economy.

Sebastien also chook mouth on UK govment efforts to dey close to China say im papa case fit even be "easy" opportunity to build ties wey go dey stronger.

Sebastien tell BBC say, "If we dey tok how to warm relationship, well I tink for most pipo wey dey hia dis, to put 78-year-old man for plan come back here no go be veri easy way for Hong Kong and China to do dat?"