Pamela Geller and Robert Spencer are due to join an EDL march in Woolwich, where Drummer Lee Rigby was killed.
The pair are prominent "anti-Islamisation" campaigners in the US.
Home affairs committee chairman Keith Vaz claims their presence will fuel hatred and is calling for them to be denied visas.
Mr Vaz said: "I am alarmed that the EDL is planning this type of march in Woolwich. It is clear that the location, motivation and attendees at this march will incite hatred.
"Adding incendiary speakers such as Pamela Geller and Robert Spencer just fuels the fire.
"Before we have to pay the costs for the extra policing required for this demonstration, the Home Secretary should consider using her discretion to ban these two speakers from entering the country.
"A ban should be enforced properly and physically stop people entering our borders."
'Extremists'
The Home Office said it did not routinely comment on individual cases but the home secretary was aware of Mr Vaz's letter and would be responding in due course.
Mrs May has the power to exclude non-British citizens from the UK if she considers their presence to be "not conducive to the public good" but she must act in a "reasonable, proportionate and consistent" way. » | Friday, June 21, 2013
THE INDEPENDENT: Right-wing American speakers planning to join the EDL's Woolwich march 'should be banned from entering the country': Keith Vaz calls on the Home Secretary to ban the founders of Jihad Watch and the American Freedom Defence Initiative who hope to join the EDL's march in memory of Drummer Lee Rigby » | Kevin Rawlinson | Friday, June 21, 2013
BBC iPLAYER: Pamela Geller and Robert Spencer visit the UK: Nihal asks whether American anti-Islam activists Robert Spencer and Pamela Geller should be banned from the UK and meets Sarbjit Kaur Athwal to talk about her book, Shamed. »
EDL Leader Tommy Robinson on BBC 5 Live (June 21, 2013) »
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