One clergyman has told a national newspaper that there are "mixed motives" in some conversions.
Dean of Liverpool Revd Peter Wilcox said his cathedral had seen the conversion of almost 200 asylum seekers in the past four years.
He told the Sunday Times: "Mixed motives are not unheard of. God alone knows the person's heard and we try to be consistent about that and not to set the bar at one height for middle-class aspiring parents seeking the best for the education of their children and the bar at another height for converts from Islam looking for asylum."
He's speaking a week after politicians warned that genuine Christian converts were being denied asylum in the UK because they couldn't answer Home Office questions like naming the 10 Commandments.
People claiming asylum in the UK are being turned away because current guidelines on "basic knowledge" mean staff ask questions such as 'when is Pentecost?', the All-Party Parliamentary Group for International Freedom of Religion or Belief said.
But Revd Wilcox told the newspaper: "I can't think of a single example of somebody who already had British citizenship converting her with us from Islam to Christianity."
He warned the Church could not refuse Baptism to someone who said they wanted to follow Christ.
A spokesman for the Home Office said: "A document such as a baptism certificate would not automatically lead to a conversion claim being accepted as genuine but is given appropriate weight when considering all the evidence."