BNP leader Nick Griffin has said people have the "right to discriminate", after he put the address of a gay couple who won a landmark court ruling on Twitter.
A court ruled a guest house owner had discriminated against Michael Black and John Morgan when she turned them away.
Mr Griffin said the men had "abused the system to persecute" the Christian owner, after earlier urging Twitter followers to hold a demonstration.
The couple, from Cambridgeshire, said any demo would be a "damp squib".
Mr Griffin is being investigated by police over the tweets published on the @nickgriffinmep account.
'Shocked to hear'
Two of the posts read: "So Messrs Black & Morgan, at [their address]. A British Justice team will come up to Huntington & give you a..." then "...bit of drama by way of reminding you that an English couple's home is their castle. Say No to heterophobia!."
An earlier tweet on the North West region MEP's account had asked for the couple's address and then said: "We'll hold demo... for rights of all home owners, gays included, to rent or not rent rooms to whomsoever they wish."
"Mr Black and Mr Morgan have the right to decide who enters their home and who doesn't, as do Christians, and that's what they are taking away," he said.
"Those two gentlemen placed themselves in the public eye and they asked for it when they used and abused the legal system to persecute an innocent Christian couple.
"It's time that the silent majority had people standing up for them so that this relentless bullying of ordinary people by activists and the left-wing judiciary stopped.
"The liberal elite simply won't listen to reasoned argument, so we have to be slightly more forceful. I believe in peaceful direct action."
Mr Black told BBC Breakfast he was baffled by Mr Griffin's tweets.
He said: "We were shocked to hear about it, of course. The more we read about it the more incoherent they seemed. We don't really know what Nick Griffin was getting at.
"He accuses us of being heterophobic, which is far from the truth, and he's accused us of trying to outlaw Christianity, which is not true either.
"The finding of discrimination protects Christians from being discriminated against as well as people who are gay or of different races or different religions."
Asked about the possibility of demonstrations, Mr Morgan said police were keeping an eye on their home.
The couple said they would give the damages they received - £1,800 each - to charity.
'Bit of drama'
Mr Griffin said: "I said we will be holding a demonstration in Huntingdon. It doesn't necessarily mean outside their house."
He claimed that the reference "give you a bit of drama" in his tweet was commenting on the fact the couple were involved in amateur dramatics, and he had only wanted a "peaceful" demonstration.
Mr Black, 64, and Mr Morgan, 59, from Brampton, near Huntingdon, went to court after they were refused a double room at Swiss Bed and Breakfast, Berkshire, by its owner.
When they arrived in March 2010, Susanne Wilkinson, who is a Christian, would not let them stay in a room with a double bed.
On Thursday, recorder Claire Moulder said that by refusing the couple access to a double room, Mrs Wilkinson had "treated them less favourably than she would treat unmarried heterosexual couples in the same circumstances".
However, the recorder accepted that Mrs Wilkinson was genuine about her Christian beliefs and had also stopped unmarried heterosexual couples from sharing a double bed.
"It was an alarming decision and that couple must have been deeply distressed by it."
Cambridgeshire Police are investigating the Twitter incident in liaison with Dyfed-Powys Police, the force where Mr Griffin lives.