The Liberal Democrats have cancelled their autumn party conference, which would have clashed with the Queen's funeral.
The party has also postponed major debates until spring following the Queen's death.
Nick da Costa, who chairs the party's federal conference committee, said the Lib Dems "want and need to show our respect to the Queen and the period of national mourning".
The conference in Brighton was due to begin on September 17 and run until September 20. The Queen's funeral will be on September 19.
Mr da Costa, in an email update, said: "The sad news of the last few days has touched our nation deeply. And we now know that the Queen's funeral will take place on the Monday of our conference."
He added: "After very careful consideration - and taking soundings from as many people as we can - the conference committee and federal board have together regretfully decided to cancel our autumn conference and postpone major debates until spring."
Earlier, Number 10 confirmed no discussions were underway about cancelling the forthcoming conference recess - which will take place immediately after the period of mourning.
There had been concerns the lengthy period of Parliamentary shutdown could lead to delays in the October 1 implementation of the cost of living plan.
But the PM's official spokesman said the government does not believe the period of mourning will impact on that date.
