Jennifer Aniston and John Mayer officially back together? After dining in New York

Jennifer Aniston and her ex-lover John Mayer have been spotted together again for the third time in a week, prompting speculation they are giving their relationship another try.

The actress and singer/songwriter joined three friends for dinner at the Sunset Tower Hotel on Tuesday night.

Their outing comes just days after they were spotted dining in Boston and New York City over the weekend.

Reunited: Before their meal on Tuesday, Jennifer Aniston (L) met up with celebrity friends at a screening of a series of short films for Glamour magazine. (R) John Mayer pictured leaving the Beverly Hills Hotel on Wednesday morning

Last month the MailOnline told exclusively how Jennifer had called her ex-partner and reinitiated contact, with them talking daily.

On Tuesday night, Jennifer met her friend Courteney Cox and her peers Demi Moore and Kirsten Dunst at the screening of a series of short films for Glamour magazine.

After mingling with her fellow female celebrities, Jennifer met up with John and three other friends at the Sunset Tower Hotel for dinner around 10pm.

An onlooker said: 'They looked like they had the best time. They were holding hands at one point and seemed very much back on.

'She seemed extremely happy to be back with him. They were close and laughing the whole time with their friends.'

The couple were spotted together at a Ray Montagne concert in Boston on October 10th and again on Saturday, had a romantic dinner at Il Mulino in New York.

As they were: Jennifer Aniston and John Mayer enjoyed a swimming pool frolic in Miami back in May

America's National Enquirer reports that the two flew from New York to Los Angeles together on Sunday night after frequently seeing each other over the weekend.

'They were very lovey-dovey,' an insider told the magazine. 'They kissed several times and hugged each other tightly. John gave her a long, lingering kiss.'

The pair, who split in August after a four-month romance, are said to have looked like lovers by the time they arrived back in California.

Jennifer had been in New York doing promotional work for her new movies, He’s Just Not That Into You and Marley And Me.

'John was relaxing after finishing his international tour, and they hooked up,' said the source.

'After spending time together under the radar in New York, they flew to Los Angeles together and looked every bit the couple they once were.'

Are they back on? Jennifer cosies up to rocker John Mayer after his performance at London's Brixton Academy in June