Prime Minister's Questions has taken place in a half-empty House of Commons, after Labour and the Conservatives told MPs not scheduled to raise a query with Boris Johnson to stay away.
Amid fears over coronavirus spreading at Westminster, the government asked politicians "respectfully" to "adhere to this advice".
Labour urged its MPs to stay away in order to avoid "crowding".
Far fewer than normal from all parties attended the session.
Amid a subdued atmosphere, Commons Speaker Sir Lindsay Hoyle promised to ensure "maximum safety" for politicians and Palace of Westminster staff.
He added: "We are all doing our best to keep Parliament sitting and to follow Public Health England guidance."
Labour leader Jeremy Corbyn praised MPs' "very sensible approach, sitting apart to stop cross-fertilising" a "horrible disease".
There has been much speculation in recent days that Parliament will close as the coronavirus crisis worsens, but there are currently no plans to do so.
On Monday, Sir Lindsay said there would be no access to the public gallery, and non-essential access would be stopped.
Several MPs have self-isolated, while Health Minister Nadine Dorries has been diagnosed with coronavirus.
Conservative Michael Fabricant tweeted that Westminster was a "major hotspot for #covid19UK".
He added: "Yesterday, a colleague suddenly sneezed in the House of Commons Chamber before he could catch it in his hands, let alone a tissue. I'll watch #PMQs from my office!"
Labour MP Harriet Harman raised concern over "packed back benches" and a "bustling tea room" at Westminster, while the public was being urged to work from home and avoid pubs and restaurants.
House of Lords Speaker Lord Fowler said: "Parliament will continue to sit. That is important. But the way we operate will have to change."