The Queen's funeral will also be a public bank holiday.
The chains will temporarily close following the delay of a number of high profile films.
Cineworld confirmed on Monday that it will temporarily shut all of its sites across the country.
The takeover would put the combined company in a better position to take on industry leader AMC Entertainment Holdings Inc , and give it more scale to fight growing competition from Netflix Inc, Apple Inc and other digital outlets. Regal is three times larger than Cineworld by market value and the combined company would have about 9,542 screens, with 7,315 screens in the United States. Cineworld Chief Executive Mooky Greidinger brushed aside those concerns.