A former leader of the Tanzim brigade - the militant wing of the Fatah political party - Barghouti was convicted in 2004 of five counts of murder, including orchestrating attacks against Israelis. Opinion polls suggest Barghouti, who is serving multiple life terms for his role in a violent Palestinian uprising against Israeli occupation, is the top contender to succeed Abbas.
"Having spent the last 15 years in an Israeli prison, I have been both a witness to and a victim of Israel's illegal system of mass arbitrary arrests and ill-treatment of Palestinian prisoners", he wrote.
Israeli authorities say approximately 1,100 of them are participating in the strike in eight prisons, NPR's Daniel Estrin in Tel Aviv reports, of the approximately 6,200 Palestinians held in Israeli prisons.
About 6 500 Palestinians are now detained by Israel.
Palestinians in the Israeli city of Umm al-Fahm have also declared a one-day hunger strike in solidarity with the Palestinian prisoners.
Other demands include installing air conditions in prisons, restoring kitchens, allowing detainees to keep books, newspapers and clothes, as well as ending the policies of administrative detention and solitary confinement.
Public Security Minister Gilad Erdan, however, disputes Barghouti's claim, saying that the proposed hunger-strike has more has to do with internal Palestinian politics rather than prisoner treatment.
Peace talks on the creation of a Palestinian state between Israel and Palestinian President Mahmoud Abbas broke down in 2014.
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Winger Arjen Robben says the Bavarians will have to raise their game having been outplayed in the second half. And as he has so much ambition. but in the end we are all happy as it is not easy to get this result here".
The strike has been called for by prominent Palestinian prisoner and leader Marwan Barghouti, who is now serving a life sentence over his role in the second Palestinian intifada - or uprising.
Palestinian officials said some 1,500 inmates affiliated with all political factions including rival Fatah and Hamas were taking part in the protest.
Barghouti began to call for a strike after talks between prisoners' representatives and the Israel Prison Service on improving prison conditions reached an impasse.
The Palestinian National Council, the legislative body of the Palestine Liberation Organisation, and Hamas have expressed their support to the strike.
Now 500 Palestinians are being held in this way, according to Mr Fares.
The Israel Prison Service threatened to punish the hunger strikers.
The issue of Palestinians held in Israeli jails is an ongoing source of tension between the two sides.
Erdan said a field hospital would be erected next to one prison - an apparent move to pre-empt transfers to civilian medical facilities, which could draw wider media attention.