OTTAWA (Reuters) - The sale of legalized recreational marijuana in Canada, which has already been pushed back once beyond the planned July start date, is set to be delayed even further, government officials said on Thursday.

A woman smokes marijuana during the annual 4/20 marijuana rally on Parliament Hill in Ottawa, Ontario, Canada, April 20, 2017. REUTERS/Chris Wattie

The ruling Liberals are sparring with the upper Senate chamber, where a draft law is currently under review. Critics in the Senate - which must approve the law - complain the Liberals are moving too quickly.

The Liberals initially planned for pot to be legalized in July but Health Minister Ginette Petitpas Taylor said the Senate vote on the draft legislation would be on or around June 7, later than expected.

If senators recommend amendments, the bill will be sent back to the House of Commons lower chamber for review, and would then have to go back to the Senate.

Asked by reporters when legalization was likely to happen, Petitpas Taylor said: “If you do the math, you can certainly see that it certainly won’t be July 2018.”

She did not give further details. The House of Commons is due to break for the summer on June 22 and will not come back until Sept. 17.

Last week, Petitpas Taylor said recreational marijuana would only go on sale a few months after it was legalized because the new retail system needs time to start working properly.

Canada would be the first Group of Seven country to legalize recreational cannabis nationally.

Some of the country’s 10 provinces - which have responsibility for setting up a system to handle sales - and police forces have argued that the timeline initially set out by the Liberals was too tight.

Medical marijuana is already allowed in Canada. The Liberals, which made legalizing recreational use part of their successful 2015 election campaign, say the new law would keep marijuana out of the hands of underage users and reduce related crime.