OTTAWA -- Prime Minister Justin Trudeau is promising that a re-elected Liberal government will introduce legislation to ensure federal laws are harmonized with the United Nations Declaration on the Rights of Indigenous Peoples.

Trudeau made the announcement Wednesday through his government's representative in the Senate, where a private member's bill on the same topic, New Democrat MP Romeo Saganash's Bill C-262, has been stalled for weeks by Conservative senators.

Their procedural manoeuvres to prevent the Senate from dealing with Saganash's bill has meant holding up a slew of other private members' bills, including one from former interim Conservative leader Rona Ambrose that would require judges to take training in sexual-assault law.

Unless passed by the Senate by the end of this week, when the House of Commons is expected to break for the summer and subsequent election campaign, the bills are effectively dead.

But if Trudeau's objective is to break the impasse and allow the Senate to get on with the other bills, Conservative Senate whip Don Plett indicated it's unlikely to work.

"Probably not," Sen. Plett said in an interview, adding that Conservative senators' priority is to debate government bills.

"When we are at the end of a session, we cannot do justice to any more than government bills."

Still, Plett indicated that the Conservatives might drop some of the stalling tactics they've been using to prolong the Senate's handling of government bills and, should all those be dealt with by Friday, he said there could "possibly" be some time left to deal with some private members' business.

However, Peter Harder, the government's Senate representative, appeared Wednesday to be writing off all the private members' bills.

"It's become clear to me that at this stage there is not a collective will to find an agreement to get Bill C-262 and other items of non-government business (done)," he told the upper house. "Regrettably, I simply do not see a path forward."

On behalf of the government and prime minister, Harder then said: "I have been authorized to formally announce in this chamber that in the forthcoming election, the Liberal Party of Canada will campaign on a promise to implement, as government legislation, the UN Declaration on the Rights of Indigenous Peoples."

Should the Liberals win re-election, Harder said the government would introduce the legislation and ensure its "expeditious" passage. The declaration asserts a range of individual and collective rights for Indigenous Peoples, including to a degree of self-government, protection for traditional land, and economic and cultural development.

Independent Sen. Murray Sinclair, a former judge who chaired the Truth and Reconciliation Commission and has been championing Saganash's bill, said Harder's message was "very heartwarming for a lot of reasons, not the least of which is it's something Indigenous groups have been asking for." He said implementing the 2007 UN declaration should have been a government bill in the first place and the failure to present it as one created the opportunity for Saganash's bill to get hung up in the Senate.

But he saved his harshest words for the Conservatives, whom he accused of acting "in the best interests of the petroleum industry" and making dishonest arguments that implementing UNDRIP could result in a veto for First Nations over resource projects.

"They know that it's not a veto. They know that the UN declaration does not create substantive rights in Canada. They know that because the Supreme Court of Canada has ruled on that issue a number of times ... So they're just using it to their political advantage to raise fears," Sinclair said.

Other private members' bills whose fate remains uncertain include one on Indigenous languages and one that would add First Nations, Metis and Inuit representatives to the board that makes decisions on national historic sites and monuments. As well, there is former Conservative Sen. Nancy Greene Raine's bill to prohibit food and beverage marketing aimed at children.

On Wednesday, Ambrose once again tweeted her displeasure that her bill on judges' education appears about to die because of "a backroom deal by a few senators."

"It's shameful that powerful senators lack the will to stand up for victims of sexual crimes," she said on Twitter.

Ambrose did not name the senators she holds responsible but Independent Sen. Pierre Dalphond, a former judge who has been championing her bill, laid the blame squarely on the Conservatives. He tried and failed Tuesday and again Wednesday to get unanimous agreement to have the Senate sit early the next day to deal specifically with Bill C-337.

Dalphond noted that Ambrose's bill was unanimously supported in the House of Commons, including by Conservative MPs, yet the party's senators continue to hold it up. He said Conservative Leader Andrew Scheer "could give marching orders to let it go, if he wanted."

"If they are not doing it, I will assume that Mr. Scheer is not opposed to that or he's a very weak leader, which I suspect he's not," Dalphond said in an interview. "I think there is some duplicity there."

Conservative senators are the last remaining unabashedly partisan group in the Senate and the only senators to sit alongside MPs in a party caucus. Plett said he's in constant communication with the national caucus and that what Conservative senators do "we do as a Conservative Party of Canada."