Jay-Z. Picture: AP

Nas has congratulated Jay-Z on "pushing the culture forward" with his new album.

The New York-born rap star has praised his one-time rival on Instagram, following Jay's recent release of his much-discussed '4:44' record, which features guest appearances from the likes of Frank Ocean, Damian Marley and Beyonce.

Nas - whose real name is Nasir Jones - wrote on the photo-sharing website: "Say what u want, but music is what's helping people unite and stay cool in these times, American music about the last thing keeping USA in good standing. Congratulations to Jayz for pushing the Culture forward with his new album 4:44 ! (sic)"

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Jay's latest album was released at the end of June and it was recently revealed his wife Beyonce listened to every song on the record before it made the final cut.

Producer No I.D. shared: "I always call Bey our de facto A&R. Pillow talk is the strongest conversation on the planet. Every song has to get past her ears, in my eyes. 

"She came by a lot and played a good part in helping us get over hurdles on certain records. Of course she's genius-level with that."

Jay-Z's title track from '4:44', features an apology from the star - who has kids Blue Ivy, five, and newborn twins with his singer spouse - to his wife, and is believed to be a direct reference to claims she made that he was unfaithful with "Becky with the good hair" on her visual LP 'Lemonade'.

Jay rapped: "If my children knew, I don't even know what I would do. If they ain't look at me the same, I would probably die with all the shame.

"You did what with who? What good is a ménage a trois when you have a soulmate, you risked that for Blue?

"I apologize, often womanize, took my child to be born, see through a woman's eyes.

"Took for these natural twins to believe in miracles. Took me too long for this song. I don't deserve you. (sic)"