CAIRO (Reuters) - Prominent Egyptian political parties on Thursday criticized President Abdel Fattah al-Sisi’s plan to transfer two Red Sea islands to Saudi Arabia and urged people to take to the streets in protest.

An aerial view of the coast of the Red Sea and the two islands of Tiran and Sanafir is pictured through the window of an airplane near Sharm el-Sheikh, Egypt November 1, 2016. Picture taken November 1, 2016. REUTERS/Amr Abdallah Dalsh

Parliament voted on Wednesday to back a treaty to hand over the two uninhabited islands of Tiran and Sanfir and Sisi is expected to ratify the decision soon.

The plan to cede the islands to Saudi Arabia, which has given Egypt billions of dollars of aid, was first announced last year and has since become mired in political protest and legal action.

The Social Democratic Party, along with several other parties and groups, called for protests on Friday.

Thousands of people backed a Facebook page named “Giving up land is treason,” which urges people to protest in Cairo’s Tahrir Square, birthplace of the 2011 Arab Spring uprising. It shows a box full of Saudi cash, which it describes as the title deeds for the islands.

Opponents of the plan say Egypt’s sovereignty over the islands dates back to 1906, before Saudi Arabia was founded.

Small demonstrations have taken place over the past couple of days, despite a state of emergency imposed by Sisi in April following church bombings that killed at least 45 Christians.

At least eight were detained for 24 hours on suspicion of illegally protesting and insulting the president, according to the state news agency MENA.

“Those who kidnap our youth from their homes because they are defending their land, shouldn’t they be called the Occupation Authority?” Zyad el-Elaimy, a liberal politician and a member of the social democratic party said on Twitter.

Elaimy said at least three members of his party had been arrested following a protest after a meeting at party headquarters on Wednesday. Security forces broke up the demonstration.

Sisi is losing much of the popularity he enjoyed when he overthrew the Muslim Brotherhood in 2013 and was lionized as the savior of the nation.

He is facing mounting criticism over the struggling economy and is seen by many Egyptians as a traitor for giving up the islands. A popular Twitter hashtag is “Sisi is a traitor.”

The Free Egyptians Party, usually supportive of Sisi, issued a strong denunciation of the treaty.

“Our patriotic and historic responsibility requires us to confirm that Tiran and Sanfir islands were and continue to be under Egyptian sovereignty,” the statement read.

The statement had also backed a court ruling which blocked the islands deal earlier this year. As legal action rumbles on, the matter will next be taken up by the Supreme Constitutional Court.

Saudi and Egyptian officials say the islands belong to the kingdom and were only under Egyptian control because Riyadh had asked Cairo in 1950 to protect them.