JERUSALEM (Reuters) - Israel's High Court on Sunday narrowly upheld a law that denies Israeli residency to many Palestinians who marry Israelis, rejecting appeals against a statute critics condemned as a violation of human rights.

The restrictions, an amendment to Israel's Citizenship Law, affect thousands of Palestinian and Israeli Arab couples. Marriages between Palestinians and Israeli Jews are rare.

"The Palestinian Authority is an enemy government, a goverment that wants to destroy the (Jewish) state and is not willing to recognize Israel," Justice Michel Cheshin said in support of the 6-5 ruling against the appeals.

In a dissenting opinion, Chief Justice Aharon Barak said the amendment violated civil rights.

The amended Citizenship Law was passed in 2002 at the height of a Palestinian uprising that began two years earlier.

It stated that only requests for residency by Palestinian women over the age of 25 and men over age 35 were eligible for approval for security reasons. Israeli authorities say Arabs with residence have taken part in attacks against Israel.

Abeer Baker, a lawyer for the Adalah organization that represents Palestinian-Israeli couples vying for Israeli residency, said the law meant that thousands of "mixed" families would either have to separate or live outside Israel. "The country is basically saying: pack up your stuff and get out of here," she said.

"That would mean they would give up their rights in Israel and their historical rights to the land."

The government could point to only 25 such residents who had been questioned for "alleged involvement in terror", said a statement by Abdalah.

A fifth of Israel's citizens are Arabs. Some have family ties with Palestinians in the West Bank and Gaza Strip. The court said the number of residency permits granted to Palestinians married to Israelis must be limited because many who received them later took part in hostile activities.

"No one is denying (Palestinians) the right to raise a family, but let them live in (the West Bank city of) Jenin rather than the Israeli-Arab town of) Uhm al-Fahm," Chesin said.

Several thousand requests for Israeli residency by Palestinians married to Israelis have been granted in the past decade, but many are temporary.

Israel bans most Palestinians from its territory on security grounds. Critics call the restrictions collective punishment.

Israelis wanting to join Palestinian spouses in the West Bank and Gaza must get approval from Israeli authorities, who have put strict limitations on access to the areas for Israeli citizens, and the Palestinian Authority.

"This is a very black day for Israel and also a black day for my family and for the other families who are suffering like us because they have been denied permission to live together," said Muad el-Sana, an Israeli Arab married to a Palestinian woman from the West Bank town of Bethlehem.

The appeals against the amendment were filed by Adalah, the Association of Civil Rights in Israel, seven legislators and several Israeli-Palestinian couples.

Justice Minister Haim Ramon defended the court's decision.

"There is no country in the world that must grant entry to thousands of citizens of a country or an entity that is in a state of war with it," Ramon told Army Radio.