While most British lawmakers are not impressed with United States presidential hopeful Donald Trump, most of them showed little interest to close Britain's doors to him during a debate on calls to ban the Republican nominee from the country.

During a three-hour debate on Monday, legislators from Britain's main parties stood to call Trump an attention-seeker, a demagogue and a fool. Many, though, argued that he should not be stifled or banned.

"While I think this man is crazy, while I think this man has no valid points to make, I will not be the one to silence his voice," said Conservative lawmaker Tom Tugendhat.

Labour Party legislator Paul Flynn, who opened the session, said Trump had already received 'far too much attention'.

"The great danger by attacking this one man is that we can fix on him a halo of victimhood and boost his popularity among supporters," Flynn said.

But another Labour lawmaker, Tulip Siddiq, supported a ban.

"This is a man who is extremely high-profile ... a man who is interviewing for the most important job in the world. His words are not comical, his words are not funny. His words are poisonous." she said.