Boris Johnson has urged the public to “behave responsibly” when pub gardens reopen and restaurants resume outdoor dining in a major easing of England’s coronavirus lockdown.

Shops deemed non-essential will also reopen on Monday, as will hairdressers, indoor gyms, swimming pools, nail salons and zoos in another stride back towards normality.

However, social mixing indoors will remain heavily restricted, with around two in five adults yet to receive their first dose of a Covid-19 vaccine and the vast majority yet to get both.

Boris Johnson’s Brexit trade deal with the EU has put the future of many exporting businesses at risk, writes our political editor, Andrew Woodcock, with 41 per cent reporting decreased overseas sales in the first three months of the new arrangements, according to a new survey by one of the UK’s leading business organisations.

The British Chambers of Commerce called on the UK government to get back round the table with the EU for fresh negotiations to lower some of the barriers to trade created by Mr Johnson’s Christmas Eve Trade and Cooperation Agreement (TCA).

While some of the collapse in trade with continental Europe was due to the Covid pandemic, the BCC said many firms were blaming Brexit for shipping delays, increased cost of transporting goods and extensive new paperwork requirements.

Gordon Brown said that tougher rules could be needed to prevent former prime ministers and ministers lobbying in the wake of the David Cameron-Greensill row.

“I can’t comment on the individual detail of this, but for me there are principles about public service – it cannot ever become a platform for private gain,” Mr Brown told BBC Radio 4’s Today programme.

“Ministers must never be lobbying, former ministers, prime ministers, must never be lobbying for commercial purposes. Current ministers should not be entertaining such lobbying.

“And if we can’t succeed in achieving this stopping by the sort of flexibility of the rules, we are going to have to pass laws to make sure that at least for say five years, no serving or former prime minister or minister, is ever lobbying for any commercial purpose within government.

“It simply brings public service into disrepute.”

The lobbying row involving the former PM gained momemtum over the weekend when it emerged David Cameron had pushed Greensill’s case with Downing Street and the health secretary, Matt Hancock.

The supply-chain finance company was rejected for the Bank of England’s Covid Corporate Financing Facility despite Mr Cameron repeatedly sending private texts to the chancellor, Rishi Sunak, pleading for the scheme to be amended so Greensill could qualify.

Records released by the Treasury this week showed that on one occasion Mr Sunak responded to say he had “pushed” officials to explore possible options.

On Sunday, it emerged that the former premier emailed a senior special adviser to Boris Johnson within hours of the rejection to argue that it was “nuts” for Greensill to be excluded and urging the government to reconsider.

First off, more on the escalating lobbying row that has forced David Cameron to comment publicly after weeks of silence.

In a lengthy statement, he insisted he broke no rules over his work for the failed finance firm Greensill, but admitted he should have communicated with the government “through only the most formal of channels”.

The former prime minister, making his first public statement since the controversy broke last month, said he understood public concern about his contact, including by text message and email, with cabinet ministers including Rishi Sunak, the chancellor, and Matt Hancock, the health secretary.

However, while acknowledging that he should have acted differently “so there can be no room for misinterpretation”, he claimed that “many of the allegations that have been made about these issues are not correct”.

Good morning and welcome to The Independent’s rolling coverage of UK political news as the row over David Cameron’s lobbying of ministers rumbles on, and the full extent of the impact of Brexit for British businesses becomes clearer.