In an interview with the BBC, Mr Hariri said: "We hear a lot of Israeli threats day in and day out, and not only threats.
"We see what's happening on the ground and in our airspace and what's happening all the time during the past two months - every day we have Israeli war planes entering Lebanese airspace.
"This is something that is escalating, and this is something that is really dangerous."
Mr Hariri also said that Lebanon was united, and that the government would stand by Hezbollah - the Lebanese militant group which fought Israel in 2006.
"I think they're betting that there might be some division in Lebanon, if there is a war against us.
"Well, there won't be a division in Lebanon. We will stand against Israel. We will stand with our own people."
His comments come just days after the foreign ministers of Syria and Israel exchanged aggressive accusations, which fuelled both media speculation and public fear about what many in the region describe as the "imminent next war".
Such hostile rhetoric is hardly new to the Middle East, and yet, because calm in this is region is so fragile, many are concerned that it could lead to a more serious confrontation.
In 2006 the Lebanese militant group Hezbollah launched a raid into Israel in which it captured two Israeli soldiers. Hezbollah also sent thousands of rockets into northern Israel.
Israel launched huge air and sea attacks on targets all over Lebanon, and then a land invasion in an attempt to secure the return of its soldiers.
More than 1,000 Lebanese, many civilians, died in the war as well as 116 Israeli soldiers and 43 civilians. In Lebanon, bridges, roads and thousands of homes were destroyed in the Israeli bombardment.
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