Organizers of the 2016 Olympics have acknowledged there are issues to be resolved in preparing Rio de Janeiro to host the event but said on Wednesday they were making progress and would deliver a "great Games".

The guarantees came a day after international sporting federations, meeting in Turkey, criticized the Brazilian government for the slow pace of work and a lack of institutional support.

"We are fully aware of the issues that need to be resolved. We are grateful for the input from all stakeholders," Rio2016 said in a statement.

"Progress has been made in the past two weeks, since the last visit of the IOC Coordination Commission for Rio 2016. We move ahead every single day.

"There is absolutely no question in our minds that Rio will deliver great Games."

Although Rio won the right to host the event in 2009, construction work at venues where eight events will take place has yet to start and the pace of progress at others is slow.

Sailors have criticized the filthy waters where the sailing events will take place and strikes have crippled some projects.

Shots were fired on Monday after construction workers downed tools and blocked roads outside the Olympic Park, one of the games' main venues.