Thousands of Myanmar's nationalist monks and their supporters prayed, clapped and held speeches at a large rally in the country's biggest city on Sunday, in a show of growing clout of radical Buddhists ahead of a Nov. 8 election.

Religious tensions are running high in Myanmar ahead of the parliamentary poll billed as the country's first free and fair election in 25 years, largely stoked by the Ma Ba Tha, an organization led by the hardline monks who called the rally.

It was a climax of their campaign to celebrate their successful push to establish four so-called Protection of Race and Religion Laws seen as targeting women and the country's Muslim minority.

The monks have emerged as a powerful force in the run up to the poll, sharply criticizing Aung San Suu Kyi's opposition National League for Democracy for opposing the laws.

"Today is the victory. Ma Ba Tha tried for many years to enact the laws to protect the country, people, nationalism and religion," said Nyanissara, a senior monk at the organization.

Thousands of devotees in white t-shirts with the Ma Ba Tha logo, monks in burgundy and nuns in pink robes crowded in front of the stage at a sports hall in Myanmar's commercial capital of Yangon. Hundreds of buses and trucks lined the streets leading to the site.

One of the bills sets punishments for people who have more than one spouse or live with an unmarried partner other than the spouse. Others require Buddhist women to register their marriages in advance if marrying a man who is not Buddhist.

The laws are dangerous for the country, set out the potential for discrimination on religious grounds and create the environment for serious communal tension, New York-based Human Rights Watch said in August.

The government denies the laws are anti-Muslim.

"We realized that laws are needed to protect the religion and nationalism. The other three religions of the country already have laws that protect them," said Ashin Tilawkar Biwonsa, chairman of Ma Ba Tha, referring to Islam, Hinduism and Christianity.

An overwhelming majority of Myanmar citizens are Buddhist.

The Ma Ba Tha said it invited representatives of the United States and western countries to the rally, but their chairs remained empty throughout the ceremony.

Aung Thein Lin, a former minister who is running in elections for the ruling Union Solidarity and Development Party attended the rally.

One of the most outspoken leaders of the group, Wirathu, on Sunday endorsed president Thein Sein, whose USDP is facing a stiff battle against the widely popular NLD.