The UK government needs to do more to protect Sikhs from race hate after the London bombings and 2001 attacks in the US, the Sikh Federation has said.
The federation said the Sikh identity was increasingly threatened
The political party said ministers had "not adequately acknowledged and tackled race-hate crimes against Sikhs and their religious institutions".
Its comments came at the National Sikh Convention in Wolverhampton on Sunday.
Partnerships to encourage UK Sikhs to join the three main political parties in greater numbers were also announced.
The Sikh Federation organised the conference at the Guru Nanak Gurdwara attended by more than 10,000 people.
The non-governmental organisation is registered with the Electoral Commission as a political party but aims to encourage Sikhs to take an increasing interest in mainstream politics.
Its chairman Bhai Amrik Singh told the convention Sikhs were "the prime target of hate crimes as the largest and most visible ethnic minority".
Despite "taking the lead in condemning terrorist attacks", Sikhs had been attacked and abused, he said.
"There is considerable frustration within the community that the government has at best been paying lip service to Sikhs since 9/11, when we were first targeted by what many termed 'mistaken identity'."
He said he believed government ministers not had publicly condemned attacks against Sikhs because they feared it would "imply it is acceptable to attack Muslims".
The Sikh Federation urged Britain to use its presidency of the European Union to defend the Sikh identity.
"In recent years, the visible Sikh identity has been increasingly challenged and threatened in the UK and other parts of the EU," it said in a statement.
It added Sikhs travelling or living in other parts of Europe were increasingly facing discrimination.
"Increased security concerns since 9/11 have unfairly affected Sikhs in many walks of life, from security cleared airport workers to members of the public trying to obtain public services in government buildings," it said.
Speakers at the convention include the shadow minister for homeland security, Patrick Mercer.
Labour MPs Pat McFadden and the chairman of the All Party Parliamentary Group for UK Sikhs, Rob Marris, also attended, along with SNP leader Alex Salmond and Liberal Democratic MEP Liz Lynne.
Mr Salmond gave his support to the Sikhs right to self-determination, a measure recently publicly backed by the Liberal Democrats and the Green Party.
The Federation also welcomed last month's formal apology by Indian prime minister Manmohan Singh for 1984 riots in which 3,000 Sikhs died.
His comments came after an Indian government inquiry said some Congress party leaders at the time had incited mobs to attack Sikhs.