The legislation was to be tabled Thursday in the House of Commons. But Tim Uppal, the minister of state for democratic reform, says his office discovered an unspecified problem with the proposed bill at the last minute.
"In our desire to rapidly incorporate recent recommendations made by the chief electoral officer, we discovered a last-minute issue in the proposed Elections Reform Act," Uppal said in a statement.
"Therefore, we are postponing the introduction of legislation. We will take the time necessary to get the legislation right."
Uppal's office isn't saying how long the bill will be delayed.
The long-awaited legislation was to incorporate recent recommendations by Marc Mayrand, the chief electoral officer, aimed at addressing problems that arose from the so-called robocalls affair.
Mayrand has warned there could be another wave of false or misleading telephone calls in the next election if tough new rules and punishments are not in place by the end of next year.
An Elections Canada report last month offered a number of ideas aimed at preventing another rash of robocalls in future campaigns.
They included penalties for impersonating election officials, wider investigative powers for elections officials and increased voter privacy.
Mayrand's office is still investigating fraudulent robocalls reported by complainants living in dozens of ridings across the country.
So far, only a junior Conservative campaign worker in Guelph, Ont., has been charged under the Elections Act in relation to fraudulent robocalls made during the 2011 election campaign.
Michael Sona, who worked on the campaign of local Conservative candidate Marty Burke, was charged earlier this month "with having wilfully prevented or endeavoured to prevent an elector from voting at an election."
Sona, who has insisted he's being made a scapegoat, is set to appear in a Guelph court May 3.
The agency's investigation has focused on the southwestern Ontario riding of Guelph, where a number of residents say they received automated phone calls from someone claiming to be from Elections Canada and directing them to a wrong or non-existent polling station.
While the phone calls appeared to target non-Conservative voters, the Conservative party insists it had no involvement in any such scheme and says it is assisting the investigation.
The Liberals, meanwhile, raised a question of privilege after Wednesday's question period over allegations the Conservative caucus was shown a copy of the draft electoral reform bill. Conservative House Leader Peter Van Loan denied the claim.
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