A group of MPs claim ministers are more interested in cash than other issues when dealing with countries like Saudi Arabia, Egypt and Bahrain.
There was "plainly a perception" that the issue of human rights had been downgraded, the Commons Foreign Affairs Select Committee said.
The omission of Egypt and Bahrain from a Foreign Office list of countries requiring special attention helped foster the idea it "has become more hesitant in promoting and defending international human rights openly and robustly", it said.
Dave Landrum from the Religious Liberty Commission told Premier's News Hour the government can do more.
He said: "We'll always be a trading nation, we'll always have an economic face towards the world, but where are our priorities.
"We have a world in which 76% of the world's population live in countries with high levels of government restrictions on religious freedom".
He added: "If we're going to make an impact in the world and have some standing in the world we have to do it from an ethical base.
"I think freedom of religion and belief, human rights and civil liberties should be at the fore front of our engagement with other countries".
Last year, the FCO's most senior civil servant made a frank admission to MPs that human rights was "not a top priority" and that the "prosperity agenda is further up the list".
Ministers deny the issue has been downgraded.
Foreign Secretary Philip Hammond said: "I do not recognise this characterisation of our human rights work.
"Improving human rights is a core function of the Foreign Office and is the responsibility of every British diplomat around the world.
"The UK supports over 75 human rights projects in more than 40 countries and this year we are doubling the funding available for human rights projects to £10 million - a true measure of the importance we attach to this agenda.
"By mainstreaming human rights within the Foreign Office, we have ensured it will always be a central part of our diplomacy, delivering tangible results."