Business Secretary Alok Sharma has been tested for coronavirus after becoming visibly unwell in the House of Commons chamber.
He was travelling home to self-isolate after he struggled during a speech at the despatch box during the second reading of the Corporate Insolvency and Governance Bill.
It comes a day after MPs approved the government's plan to end virtual voting in the Commons.
A spokeswoman for Mr Sharma said: "In line with guidance he has been tested for coronavirus and is returning home to self-isolate."
During the debate, he was seen wiping his face with a handkerchief several times and his opposite number in Labour's shadow cabinet, Ed Miliband, passed him a glass of water at one point.
A House of Commons spokesperson said: "The House's priority is to ensure that those on the estate are safe while business is facilitated.
"We have closely followed guidance from PHE on action to take following a suspected case of COVID on site, including additional cleaning.
"Our risk assessment outlines the measures we have already put in place to reduce the risk of transmission in parliament."
Labour shadow minister Toby Perkins had raised concerns over Mr Sharma's appearance in the Commons earlier in the day.
"This is not okay. If he has symptoms that could be COVID-19, it's not up to him to soldier on, he is jeopardising the health of everyone who he comes across and everyone else who touches that despatch box and every door handle he touches etc," Mr Perkins tweeted.
"Maybe he's had a test and knows it's not that, but if so he should confirm that to people watching, otherwise the message again goes out that what the government says and means about what to do if you have symptoms are two different things."
Digital voting in the Commons was ended on Tuesday when MPs approved a government motion introduced by Commons Leader Jacob Rees-Mogg despite widespread objections.