US Ambassador Thomas Krajeski came under fire from a Bahraini MP during parliament's weekly meeting yesterday.
National Independent Bloc president Hassan Al Dossary, who is also parliament's public utilities and environment affairs committee chairman, accused the ambassador of leading a "war" against Bahrain.
He accused Mr Krajeski of interfering in Bahrain's internal affairs, following claims that opposition groups taking part in the National Dialogue were being fed advice and support by the US.
"There is a war on Bahrain led by Mr Krajeski and as representatives of the public we don't agree and will never agree with this," said Mr Al Dossary at the beginning of yesterday's parliamentary session.
"The ambassador is using war mechanisms through his European Union allies and paid international organisations to interfere in Bahrain's affairs and we can't stay quiet as this continues.
"This diplomat has crossed all red lines as he runs the National Dialogue, distributes letters and recommendations in English to participants, according to evidence we have.
"We don't want a statement being issued by parliament condemning his interference, a strong decision has to be taken by MPs and sent to the government to stop this man from further damaging the nation."
Mr Al Dossary's comments follow allegations on Sunday by MP and dialogue participant Latifa Al Gaoud that a key opposition document submitted to the talks had been drafted in English before being translated into Arabic.
Ms Al Gaoud, who is a member of the National Independent Bloc, said some of the words had not even been translated into Arabic and suggested the document had been drawn up with help from the US Embassy.
Mr Krajeski caused anger last month when he was spotted at the National Dialogue venue on the same day that a session of the talks was taking place.
He was seen leaving just moments before talks were due to start, but a US Embassy spokesman claimed he was there for a private meeting and did not meet dialogue participants.
Among those also seen at the meeting attended by the ambassador was editor-in-chief of opposition newspaper Al Wasat Dr Mansoor Al Jamri.
When contacted by the GDN about the allegations, the US Embassy said: "The US has shared its strong support for the National Dialogue in Bahrain with all the participants and continues to encourage them to look for positive opportunities to advance their discussions on behalf of all Bahraini citizens."