However, with the Palestinian Islamist group Hamas announcing a resumption of suicide bombing inside Israel after many years and with Israeli air strikes still pounding Gaza, there is little sign of conciliation.
Hamas and another militant group, Islamic Jihad, said they were behind a blast near a synagogue in Tel Aviv on Sunday that killed the bomber and wounded one other person.
Suicide bombings "will return to the forefront" while the Gaza war continues, Hamas said in a statement.
The talks in Qatar last week paused without a breakthrough, but the negotiations are to resume this week based on a US "bridging proposal".
Blinken met Israeli President Isaac Herzog and Prime Minister Benjamin Netanyahu on Monday.
"This is a decisive moment, probably the best, maybe the last opportunity to get the hostages home, to get a ceasefire and to put everyone on a better path to enduring peace and security," Blinken told reporters before meeting Herzog.
Months of on-off talks have circled the same issues, with Israel saying the war can only end with the destruction of Hamas as a military and political force and Hamas saying it will only accept a permanent, and not a temporary, ceasefire.
There are disagreements over Israel's continued military presence inside Gaza, particularly along the border with Egypt, over the free movement of Palestinians inside the territory, and over the identity and number of prisoners to be freed in a swap.
Despite US expressions of optimism, both Israel and Hamas have signalled a deal will be difficult.
With AAP.