Ministers have been accused of making a “mockery” of quarantine rules after it was announced some business executives travelling to England will be able to temporarily leave self-isolation.

Rules for those arriving from amber list countries have been changed to let visitors entering the country bringing “significant economic benefit” interrupt their up to 10-day stay at home for important business activities.

The business secretary, Kwasi Kwarteng, is understood to have backed the change, which was announced on Tuesday, due to concerns the UK was missing out on major investments and new jobs because of current quarantine rules.

Executives working at multinational and international companies who want to use the exemption must get written permission from the government in advance of their journey, and must still get a negative Covid-19 test result before departing, get tested again when they arrive in England and complete a passenger locator form.

To be eligible, they must show their work in the country would probably preserve an existing UK-based business with at least 500 employees, or create a new one within two years. Any executives conducting work that can be done by telephone or remotely will not be eligible.

All meetings must be Covid-secure and bosses must return to their self-isolation afterwards.

A government spokesperson said quarantine would only be waived in “truly exceptional circumstances” and claimed many other countries had introduced similar policies.

The decision came on the same day the UK reported another 20,479 Covid cases and 23 deaths. This was a doubling of last Tuesday’s figures, 11,625, but also four fewer deaths.

The exemption used to apply to executives at businesses with just 50 staff – so the threshold has been significantly raised to stop abuse by those working at smaller companies. It was suspended in January, when England went into its third national lockdown.

Angela Rayner, Labour’s deputy leader, tweeted that “this just takes the pi**”.

She said: “It is the lowest-paid working people who have got our country through this crisis, risking their lives on the frontline. This is an offensive slap in the face for them and shows this government’s true colours.

“Yet again it is one rule for those at the top and another for everyone else. This makes a total mockery of the sacrifices of the British people during this pandemic and this double standard is an insult to frontline workers that the British people will rightly be disgusted by.”

Other senior Labour figures expressed similar sentiments. Andy Burnham, the mayor of Greater Manchester, said it was the “wrong move at the wrong time”. Paula Barker, the Labour MP for Wavertree, said it was proof of the “same old Tories’” behaviour of “one rule for themselves and their elite friends, another for everyone else”.

Nick Timothy, a former No 10 co-chief of staff to Theresa May, said: “It’s time to get back to normal for everyone, not just elites.”

Bosses hoping to use the loophole to attend a routine board meeting will be disappointed as the government has said this is “ineligible activity”. But a meeting to make a decision on whether to invest in a new UK division could be accepted.

Business leaders have been primarily carrying out activities remotely during much of the pandemic.

Airlines have been pushing hard for restrictions on international travel to be eased because sales of business-class and first-class seats – which generate the biggest profits – have plunged as companies adopt remote working.

Industry groups gave the quarantine change a lukewarm welcome, but said far more needed to be done to revive international business travel and trade.

Matthew Fell, UK policy director of the CBI, said it was a “step towards taking the pragmatic and truly risk-based approach needed for business travellers in the coming months”. But he added: “It must not be forgotten that there is also a clear need for business travel beyond entrepreneurs and senior industry leaders and many firms will still be crying out for greater ease of movement to oil the wheels of the economic recovery.”

The Institute of Directors chief economist, Tej Parikh, said it was important that there were efforts to restore normality but other firms should not be overlooked. “Medium-sized enterprises will be the powerhouses of our economic recovery, so initiatives that effectively lower quarantine requirements for executives in large businesses seem arbitrary.”