A group of MPs and peers sanctioned by China have expressed serious concerns about the Chinese Government being invited to the Queen’s funeral.

Senior Tory MPs Tim Loughton and Sir Iain Duncan Smith wrote this week to the Commons Speaker and Lord Speaker, calling it “extraordinary” that Chinese representatives should have received an invitation.

The letter, also signed by crossbench peer Lord Alton and Labour peer Baroness Kennedy, says: “We are greatly concerned to hear that the Government of China has been invited to attend the state funeral next week, despite other countries Russia, Belarus and Myanmar being excluded.

“Given that the United Kingdom Parliament has voted to recognise the genocide committed by the Chinese Government against the Uighur people it is extraordinary that the architects of that genocide should be treated in any more favourable way than those countries who have been barred.”

The Chinese Government is reportedly considering sending a delegation to the funeral on Monday in Westminster Abbey but is is unclear whether President Xi Jinping will attend.

The Chinese leader is currently meeting Russian president Vladimir Putin at a summit in Uzbekistan.

Chinese vice-president Wang Qishan is expected to attend, the South China Morning Post reported, citing diplomatic sources.

In response to the letter from MPs and peers, Downing Street said: “First and foremost it is for the Palace on the invite list, this is inviting heads of state, world leaders to the funeral of Her Majesty so it is for them to set out the guest list.

“And as a convention those we have diplomatic relations with are invited in the main.”

The UN recently published an assessment of human rights concerns linked with the Xinjiang region of China, and concluded “serious” violations had been committed there linked to Beijing’s so-called counter-terror and counter-extremism policies.

As foreign secretary, and during her summer-long campaign to become Prime Minister, Liz Truss pushed for a hard line against the Chinese Government.

And earlier this month, Tory MP Tom Tugendhat – now security minister – urged the Government to look at banning the import of all cotton products produced in the Xinjiang region as a response to the country’s treatment of Uighur Muslims.

Mr Loughton said he was unsure whether the decision to invite China to the funeral was “a conspiracy or cock up”.

“I don’t know why this has happened,” he told BBC Radio 4’s World At One programme.

“I don’t know whether it’s a conspiracy or cock up. You cannot have a golden age, normal relations, with a country which has now been exposed as committing the sorts of atrocities that it has, not least the genocide against the Uighurs.”

Asked if he wanted the invite to be rescinded, he said: “Yes.”

In their letter, the parliamentarians say they have written to Foreign Secretary James Cleverly to express their concerns.

“It is also particularly inappropriate given that seven parliamentarians including ourselves remain sanctioned by the Chinese Government and you along with the Lords Speaker have quite rightly barred the Chinese Ambassador from attending the Palace of Westminster whilst these unjustified sanctions remain in place,” they write.

“It may well be as part of the arrangements for foreign dignitaries attending the state funeral that facilities at the Palace of Westminster will be made available to them before or after attending the service at Westminster Abbey.

“I am sure you will agree that it would be wholly inappropriate that any representative of the Chinese Government should be able to come to the Palace of Westminster and that you can give us your assurance that this will not happen.”

Invitations to the Queen’s state funeral have not been sent to Russia, Belarus or Myanmar while Iran will only be represented at an ambassadorial level, it is understood.

On the relationship between China and Russia, former national security adviser Sir Mark Lyall Grant said the countries are closer than they have ever been but there are “limits in their friendship”.

“China is, I think, worried by Russia’s expansionist sort of movement in the West, and is not going to offer, I don’t think, any material support to Putin in Ukraine,” he told the BBC’s World At One.

“Certainly there’s some political support, some rhetorical support, but nothing more than that so far.”