BANGKOK (Reuters) - Restrictions on Thai political parties will only be lifted after royal ceremonies that will not happen before late this year, Prime Minister Prayut Chan-o-cha said on Tuesday (April 11).

Parties have been banned from meeting or campaigning since a 2014 coup, but a military-backed constitution was signed last week in a step towards restoring democracy after the 12th successful coup in little over 80 years.

Political parties have urged the government to allow them to operate freely.

Prayut said restrictions would remain until after the cremation of late King Bhumibol Adulyadej, tentatively set for October, and the coronation of King Maha Vajiralongkorn, for which no date has been set.

"Campaigning should happen after," Prayut told reporters.

King Bhumibol's death last October after more than seven decades on the throne sent Thailand into mourning.

A date has not yet been fixed for a general election, which had initially been promised by the junta for 2015. According to the new constitution, it could take another 19 months before the vote happens.

The Pheu Thai Party of former prime minister Yingluck Shinawatra, whose government was overthrown in the 2014 coup, said some restrictions should be lifted. "We understand that there may be caveats and boundaries due to the sensitive timing, but we want the government to understand us too," said party lawmaker Amnuay Klangpha.

The Democrat Party, the other main political party, has also said it wants the government to lift the restrictions sooner.

The army seized power in the name of ending political turmoil and the junta's critics say the new constitution will allow the generals to keep a strong grip even after an election.