Sefton Central MP Bill Esterson has backed residents of Hightown who oppose the building of a 70ft mast in the centre of the village.
The MP wrote to the Planning Inspector to object to an appeal by Vodafone after its application to Sefton Council to build the mast was refused.
Mr Esterson said refusal was the right decision and that the mast would have "a hugely detrimental visual impact".
He wrote: "This mast would be nearly 70 feet high and would be placed in the centre of the village having a hugely detrimental visual impact.
"There are around 900 homes in Hightown. More than 500 residents signed a petition objecting to this application. Another 21 individual objection emails were received and Sefton Council rightly in my view rejected the application.
"The National Planning Policy Framework states that the numbers of radio and telecommunications masts and sites for such installations should be kept to a minimum consistent with the efficient operation of the network; existing masts, buildings or other structures should be used unless the need for a new site has been justified; and where new sites are required, equipment should be sympathetically designed and camouflaged where appropriate.
"In Hightown there is already an EE mast on the outskirts of the village disguised as a tree. I would suggest this site would be preferable and would better meet the guidance of the NPPF.
"A 70ft mast in the centre of Hightown village would tower above nearby properties and would in my view constitute inappropriate development in a residential area.
"Please accept this correspondence as an objection to this appeal."
The MP added: "I hope the Inspector will listen to the people of Hightown. This mast would be totally out of keeping with the local area."