LONDON (Reuters) - England needs tough restrictions after its current lockdown ends if hospitals are not to become overwhelmed, a senior minister said, as Prime Minister Boris Johnson wrote to lawmakers to say the measures would end in February to try to quell opposition. Britain upped preparations for a vaccine roll-out on Saturday as Johnson named Nadhim Zahawi as a new health minister to oversee its deployment and the Financial Times reported that the UK is set to approve the BioNTech Pfizer vaccine next week. But despite progress on the vaccine, the government still needs to convince lawmakers to back its new tougher tiered measures which will put 99% of English people into the highest two levels of restrictions when the current national lockdown ends on Dec. 2. Sky News reported that Johnson wrote to lawmakers ahead of their vote on the new measures on Tuesday to say that the tiered approach has “a sunset of 3 February” and they will be reviewed every two weeks before then. Lawmakers will then vote again on Jan. 27, according to the letter. Cabinet Office minister Michael Gove wrote in the Times newspaper on Saturday to warn that without further restrictions on most of England’s population hospitals would be overwhelmed. He urged lawmakers to back government plans. More than 20 million people across large swathes of England will be forced to live under the toughest tier of coronavirus restrictions. A growing number of lawmakers in Johnson’s Conservative party have voiced opposition to the tiered restrictions plan. Some argue that the areas they represent have low infection rates but face the toughest rules, while others say the new measures will cause unnecessary economic harm to local businesses. There is also some public opposition to the restrictions. Police in central London said they made 155 arrests during anti-lockdown demonstrations on Saturday. Gove said the level of infection across the country remained “uncomfortably and threateningly high”. “These new tiers, alongside the wider deployment of mass testing, have the capacity to prevent our NHS being overwhelmed until vaccines arrive,” said Gove.