Black police officers are to actively discourage new recruits from joining the Met.
The Metropolitan Black Police Association claims the force has "a hostile atmosphere where racism is allowed to spread".
The association said that it would boycott all recruitment drives initiated by the Metropolitan Police Service (MPS) to attract black and ethnic minority recruits and police staff.
"The Metropolitan Police under the current management and supervision of the Metropolitan Police Authority (MPA) have made the working environment for its existing black staff a hostile atmosphere where racism is allowed to spread and those who challenge it are either suspended, told to shut up or subtly held back in relation to career development," its statement said.
"We would be failing our duty as an association if we did not share our current experiences with those who want to join the MPS.
"The boycott and our active discouragement will continue during Black History Month and beyond until the Metropolitan Police leadership and the MPA convince us that they care about race and equality for its workforce and the people of London. We will not put up or shut up to racism and inequality."
The association pledged "to take out a series of actions in the foreseeable future in support of our goal".
The Society of Black Lawyers - which has requested the Equality and Human Rights Commission investigate allegations of racism within the MPS and MPA - has backed the boycott.
Metropolitan Police Deputy Commissioner Sir Paul Stephenson said: "I very much regret the Met BPA's decision and we must find a way to work through this together.
"Much has been achieved since the Macpherson report was published but I am not complacent and recognise more must be done not only by us but also with the Met BPA's full support and engagement.
"The MPS now has three times as many black and minority ethnic officers as 10 years ago and approximately 20 per cent of new recruits in to MPS police training come from a black or minority ethnic background."
He added that he welcomed the MPA's plan to hold an inquiry.
"I believe it will assist in making progress and provide the reassurance the Met BPA are looking for."
Commentary: Several black and minority ethnic people die in police custody every year in the UK. Recently, a Ghanaian died during arrest by Immigration police in London, others have been maimed and injured in the process. A large majority of police officers generally think all black people are the same: "as thick as two planks of wood, often stand in street corners, smoking cannabis, and other drugs, excitable, loud and throw our hands about when talking." A black person is 6 times more likely to be stopped than a white person. When stopped, he is more likely to be searched. He is also more likely to receive a custodial sentence when the matter gets to court. A disproportionate number of blacks are incarcerated in male and female jails, mental health institutions, care homes or on remand, due to the coercive and discriminatory attitude of the British police. Attitudes have not changed much since the Macpherson Report, following the death of Stephen Lawrence. The Met was officially declared institutionally racist. The time has come for us all to debate the racism facing our black brothers and sisters within the Met and to call for equality. Let us look at their recruitment procedures, promotion, pay and conditions. Let us examine fair treatment of members of the black community. They should refrain from criminalising, antagonising, taunting and victimising our youth, malicious prosecution, in some cases, planting drugs on them even when they are deceased and, destroying vital CCTV evidence. The list goes on and on. It is scandalous.