Some England players will not wear rainbow laces against Australia on Saturday, citing comfort issues.
The Rugby Football Union gave players the choice, with flanker Sam Underhill and centre Ben Te’o opting against it.
“I won’t be wearing them but I fully support the LGBT community,” Underhill said.
“That’s something we are all very, very keen that people know.”
The Rainbow Laces campaign began in 2013, when gay rights group Stonewall invited footballers in England and Scotland to wear them.
England and Australia players will be allowed to make an individual decision for their autumn international at Twickenham (15:00 GMT kick-off).
Underhill, 22, says his decision not to is because of “the thickness of the laces”, adding: “They are actually really uncomfortable in my boots – and they are really long.
“On game day, little things can make quite big differences. It’s a fantastic cause to support.
“If it was on a shirt or something like that, I don’t think anyone would say anything. But it’s just the fact that you get two bits of kit that are yours – your boots and your gum shield.
“Changes in things such as your laces can make a big difference to a player.”
Te’o, 31, said: “I haven’t got the laces at the moment. I’ll just leave my boots as they are, as I’ve had them for the autumn.”
Australia full-back Israel Folau, who was criticised after a social media post earlier this year suggested gay people would end up in hell, has declined to wear the laces.
Serge Simon, French Rugby Federation vice-president, posted on social media: “Dear Gareth Thomas, all French Rugby is with you.
“To show our support, the French rugby players will wear a rainbow shoe lace during the France v Fiji game on Saturday night. We’re all in with you in this matter.”