Iain Stewart, MP for Milton Keynes south, said he would “wholeheartedly” support the amendment in urging the government to go further in pardoning gay men convicted of now abolished sexual offences.
He was joined by former minister Chris Bryant who recalled gay and bisexual MPs, insisting they and others should receive “something that feels like an apology”.
Tory former justice minister Crispin Blunt also warned the government’s proposals do not have the desired “symbolic effect”.
The government has been accused of trying to “hijack” the so-called Turing’s Law after it announced on Thursday plans for thousands of gay and bisexual men convicted of crimes which no longer exist to be pardoned.
It follows the pardoning of World War Two code-breaker Alan Turing, who spent much of his life working in Bletchley, for gross indecency after he was castrated for being gay.
But the SNP’s John Nicolson has brought forward a private member’s bill which goes even further, proposing an automatic pardon for the living too.
He was urged by Justice Minister Sam Gyimah to withdraw his bill.
But Mr Bryant said the proposal should progress, saying: “Alan Turing was just one wronged gay man amongst thousands.
“The British state owes an apology and pardon to the ordinary men who were criminalised for being who they were, just as much as it owed an apology to Alan Turing.”