"We can now have a period of calm where we hope we can genuinely take forward modernisation in a way that puts the union at the centre," he said.
Yet he added that the union recognised the forthcoming negotiations would be difficult, saying the dispute had been "bitter".
"It will take exceptional efforts to rebuild trust," he said. "But we will work very hard to ensure that the agreement stays on track."
Royal Mail managing director Mark Higson said he now looked forward "to positive and constructive discussions on the next stage of Royal Mail's modernisation plan".
"I'm delighted for our customers and our people that we've got back to a sensible agreement with the CWU that will allow us to deliver a great Christmas while getting on with the vital talks about the longer term future of Royal Mail," he added.
The CWU also confirmed that it was not now pressing ahead with its legal challenge to the Royal Mail over its policy of employing temporary workers to deal with the postal backlog.
Christmas deliveries will now be unaffected
It had previously been due to go to the High Court on Friday, accusing Royal Mail of using the temporary staff to try to break the strike, something Royal Mail strongly denied.
Mr Ward also issued a fresh plea for the government to help tackle the Royal Mail's £10bn pension fund deficit, saying that until that problem was dealt with, it would be difficult to overcome the "challenges" ahead.
Although the government owns Royal Mail, it has so far refused to get involved with the pension issue.
Business Secretary Lord Mandelson said he welcomed the news that further strikes had been called off.
"It's important that both sides now keep talking about the next phase of modernisation which is vital for the company's future," he said.
"Strikes do nothing to help Royal Mail, its business, its future prospects and of course the jobs and livelihoods of those who work in Royal Mail."
Until the latest announcements, CWU members had held five 24-hour strikes over the past two weeks, which involved members in different roles striking on different days.
The strikes that had been planned for Friday and Monday were to be all-out action involving up to 121,000 union members on each day.
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