MPs should be made to wear masks in Parliament after July 19, unions have told the House of Commons Speaker Sir Lindsay Hoyle.
Sir Lindsay has written to MPs explaining they will be "encouraged" to continue wearing masks until July 22, when Parliament breaks for its summer recess, but all other staff must wear one while on the Westminster estate.
"This is a stark example of how rules in Parliament apply only to some and not to others," Unite, House Trade Union Side and GMB unions said in a joint letter to the Speaker.
The unions urged Sir Lindsay to "urgently reconsider the guidance provided to Members so that all staff and members are content that the appropriate measures have been taken to protect their health."
They challenged a claim that the lack on an "employment relationship" between Parliament and MPs means there is no ability to force them to wear a mask and called for the extension of dress code rules to MPs who try to enter the Chamber without a mask.
Currently, MPs who are not exempt must have their face covering on when not speaking in a debate in the Commons, while it is also recommended that they are adorned when moving about the estate.
On Tuesday a union representing civil servants said it plans to "name and shame" MPs who refuse to wear face coverings in Parliament once legal requirements are dropped.
FDA general secretary Dave Penman said he would be writing to MPs warning them that his union was willing to "call out" those ditching their masks.
It comes as Labour leader Sir Keir Starmer’s spokesperson said the party’s MPs will be asked to continue wearing face coverings and uphold social distancing in Parliament after July 19.
Sir Keir’s spokesperson told reporters: "It does seem bizarre and wrong where you’ve got a situation where it is one rule for MPs and another for staff.
"If the advice is that staff should be wearing them, then I don’t see why the same should not apply to Members of Parliament, and certainly the Labour Party will be encouraging our Members of Parliament to continue to wear masks and observe sensible measures like social distancing."
Asked whether it would be an instruction to MPs, he replied: "We will be asking them to do so, yes."
A spokesperson for the House of Commons Commission said: “Throughout the pandemic, the House of Commons' response has been informed by and in line with government regulations and guidance.
"For the final four days before the House rises for the summer recess, Members are strongly encouraged to continue wearing face coverings.
"All others on the estate will be required to wear them while moving around the estate or entering venues.
"The Commission would like to thank all House staff for their continued hard work during the pandemic."
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