The US state department has criticised Israel's treatment of thousands of African asylum seekers who it says are being denied basic social services.
The US annual report on human rights says that many are refused refugee status, so cannot access health care.
It is estimated that up to 60,000 migrants, most from Sudan and Eritrea, have entered Israel in recent years.
The report also criticises Israeli government officials for referring to migrants negatively as "infiltrators".
It cites statistics from the UNHCR which show Israel approved just one of the 4,603 new asylum applications it received last year.
The data also shows that more than 6,000 previous cases are still pending.
The US state department notes that Israel has ended the practice of immediately returning asylum seekers who had arrived through Egypt.
In 2010 Israel approved the construction of a barrier along its border with Egypt to try to stop migrants entering the country. Once complete it will run for 250km (155 miles) and include an electric fence and surveillance technology.
But it shows concern over regulations that allow the authorities to reject applications without appeal, and that there is no independent appeal process.
The report acknowledges that once recognised refugees are allowed to work and access social services, but non-governmental organisations are campaigning for greater access to health care, particularly for victims of abuse.
Some right-wing politicians have been criticised for stoking up hatred with speeches comparing "infiltrators" to cancer and calling for migrants to be expelled.
Officials claim the overwhelming majority of migrants are not fleeing persecution and war but that they are economic migrants looking for jobs and a better life.
Tensions in Israel have been rising and on Wednesday a demonstration in Tel Aviv against African migrants turned violent - shop windows were broken and cars were damaged.
The following day Israeli Prime Minister Benjamin Netanyahu condemned the violence saying: "I want to make clear that there is no place for the statements nor the actions which we saw last night... we will resolve the problem and we will do it responsibly".