THE Prime Minster's official spokesman has refused to say whether Boris Johnson attended a garden party in his own home at the height of lockdown. 

Speaking to Westminster journalists this morning, the spokesman was asked a myriad of questions on the affair which has prompted huge criticism of the Prime Minister.

It is understood as many as 100 people were invited to attend a socially-distanced gathering at No.10 on May 20, 2020, and told the bring their own alcohol. 

Around 30 people are reported to have turned up.

The spokesman said he was unable to comment on multiple questions due to an ongoing investigation into possible breaches of lockdown by senior civil servant Sue Gray. 

Asked whether the PM was at the event, as has been speculated, his official spokesman said: "Whilst this investigation is ongoing I can't comment on the reports and claims, including those we've seen today.

"It wouldn't be appropriate to do so. I appreciate there may be significant number of questions but that remains position." 

Asked if Mr Johnson acknowledged it made it appear that he had "something to hide" by refusing to say whether he was at the party, the spokesman said: "I think what everyone wants to do is establish the facts through this independent review and for those facts to be set out clearly, once that work is concluded."

Asked if Mr Johnson had received assurances that there was no party on May 20, the spokesman repeated that he would not comment. 

The spokesman was then asked if he had asked Mr Johnson if he attended the party, to which he said: "Well, I'm not going to get into the conversations I've had with the Prime Minister. Again, what's right is that the investigation is able to carry out its work." 

When questioned on whether the Prime Minister had "lied to the Commons or to the public" over parties at Downing Street, the spokesman said: " As I say, again, while I don't want to repeat myself, The Prime Minister has addressed those sorts of questions on numerous occasions. I don't have anything to add to that."