But he said a long-term truce would be possible if Israel accepted conditions including a return to its 1967 borders.
Israel's acting PM said if he won next month's poll, Israel would retain West Bank settlement blocs and Jerusalem.
However, Ehud Olmert said Israel would be prepared to give up parts of the West Bank where most Palestinians were living.
His interview on Israel television was his first since taking power a month ago following Ariel Sharon's massive stroke.
'Recognise rights'
Mr Meshaal said he wanted to send a message to the next Israeli government that Hamas would be ready to talk if Israel met certain strict conditions.
Hamas supporters at a rally in Gaza City
Profile: Khaled Meshaal Meshaal interview transcript
The most important of these was that Israel must withdraw to the boundaries it had until the 1967 Middle East war, Mr Meshaal told the BBC's Middle East editor Jeremy Bowen.
Hamas would then "possibly give a long-term truce with Israel", he said.
"This is a position that Hamas could take, but not now, only after Israel recognises the rights of the Palestinians, to show and confirm its willingness to withdraw to the 1967 borders," he said.
Mr Meshaal said such a move by Israel could create conditions for the international community to find a solution for all of the region's problems.
Our correspondent says that by putting the onus on the international community, the Hamas leader seems to be displaying a willingness to accept international mediation.
But Mr Meshaal, who lives in exile in the Syrian capital, Damascus, also warned that the militant group was capable of leading the Palestinians in a long fight that they would be better able to bear than Israel.
He and other Hamas leaders are in the Egyptian capital, Cairo, to discuss the next step after their 25 January election win over rivals Fatah.
Jerusalem issue
Hamas has largely observed a truce in its fight with Israel for the past year.
Now it's time for Israel to do what they said they would never do and enter dialogue with Hamas Darryl LeCount, Paderborn, Germany
However, Israel believes offers like the latest by Mr Meshaal are a ruse to allow Hamas to gather its strength, since its charter calls for the destruction of the Jewish state, our correspondent says.
Speaking on Channel 2 TV, Mr Olmert said Israel would retain "united Jerusalem", which would include occupied East Jerusalem, if his Kadima party won Israel's general election on 28 March.
But he said Israel would disengage from parts of the West Bank where the population is mostly Palestinian, at the same time as retaining its three main settlement blocs.
Israel has occupied East Jerusalem since 1967. It annexed the area in 1981 and sees it as its exclusive domain.
Under international law the area is considered to be occupied territory.
East Jerusalem is often called Arab East Jerusalem because the majority of its residents are Palestinian, and Palestinians hope to establish their future capital there.
It's a trick.
Stalling tactics.
Yossi Beilin will be dropping his drawers for servicing by Hamas very soon.
In a war, the losers do not get to dictate terms of surrender to the winner.
At least they won't say: "You can trust us! We're not like the others!"
OK Israel removed all settlements from Gaza. What good faith step is Hamas going to make?
A truce with Hamas/Islam is fools gold.
Israel is winning.
Israeli definition of a cease fire: "We cease, they fire"
NEVER!
Those maniacs probably think that they'll be dictating terms.
We really should allow Israel to end this nonsense once and for all.