Qatar's ruler on Tuesday hit out at "double standards" unleashed in an "unprecedented campaign" of criticism over his country's rights record ahead of this year's football World Cup.

Just 26 days from the first game, Sheikh Tamim bin Hamad Al-Thani gave a rare public airing of the Islamic country's frustration following years of attacks over its treatment of foreign workers and over LGBTQ and women's rights.

"Since we won the honour of hosting the World Cup, Qatar has been subjected to an unprecedented campaign that no host country has faced," the emir told Qatar's legislative council.

Qatar initially accepted negative commentary "in good faith" and "even considered that some criticism was positive and useful, helping us to develop aspects that need to be developed," the ruler said.

"But it soon became clear to us that the campaign continues, expands and includes fabrications and double standards, until it reached an amount of ferocity that made many wonder, unfortunately, about the real reasons and motives behind this campaign," he said.

Fifa awarded the World Cup to an Arab country for the first time in 2010. Qatar has since spent tens of billions of dollars on preparations but has faced intense scrutiny over human rights.

Hours after the emir spoke, the challenges facing authorities when one million fans are expected to converge on Qatar were highlighted as a veteran British campaigner protested in Doha over the country's criminalisation of homosexuality.

Peter Tatchell staged the protest outside Qatar's National Museum, holding a banner that read: "Qatar arrests, jails and subjects LGBTs to 'conversions'".

The government had angrily rejected a report released on Monday by the Human Rights Watch group which said police have arbitrarily detained and abused members of the LGBTQ community ahead of the World Cup. Homosexuality is illegal in Qatar and critics say women's rights are restricted by male guardianship laws.

Tatchell, 70, was arrested for a similar protest before the 2018 World Cup in Russia. This time, witnesses said police advised him to fold up his banner before they walked away.

The emir also said the World Cup was a chance for Qatar to show "who we are, not only in terms of the strength of our economy and institutions, but also in terms of our civilisational identity.

"This is a great test for a country the size of Qatar that impresses the whole world with what it has already achieved."

Fifa president Gianni Infantino has defended Qatar and said the World Cup will be the "best ever, on and off the field". (AFP)