Lance Bass is hoping to become a dad by the end of 2018

He said: "We're already headed down that route [Surrogacy].

"Not picked the surrogate yet, but hopefully ... We hopefully will be pregnant by the end of next year. It's what I'm hoping, yes. Who knows what's going to happen?"

The 'It's Gonna Be Me' hitmaker said that he wouldn't mind if the mother becomes pregnant with twins as his 30-year-old spouse is one, as long as they were healthy.

He told PEOPLE magazine: "I guess we'll look at the embryos of course, and just see which ones are the healthiest.

"No, actually it doesn't scare me because my husband's a twin. He knows exactly how to handle twins."

Lance is looking forward to a fun-filled festive period, which could potentially be their last as just a couple.

Asked how they are spending Christmas, he said: "Look, we have fun, and even when we become parents, I think it's very important to give yourself balance so make sure that you still have your friends around and you have fun every once in a while, but of course it all is about your kids. Your life is over."

The pop star previously revealed he and Michael intend to use a surrogate mother to have their baby like many other gay couples.

He explained: "There's an amazing company that a lot of people have been using - Neil Patrick Harris and everyone used this company. They set you up with a surrogate, and there's all different ways of doing it. Surrogates that you never have to meet - but, of course, I want them in my life. I want to know who's donating the egg.

"You can donate an egg, put it in someone else. You can have twins, you can make sure that one is mine and one is Michael's. I mean, there's so much you can do."

Lance is very "excited" about the prospect of starting a family because he knows Michael will be the "best" dad.

He said: "I'm excited because I know Michael will be the best dad ever. That's one of the reasons I wanted to marry him. So I'm excited to start this family, because I think all of us selfishly want to try to raise the best kid possible, just so we can have a better person in this world, helping out. And so I hope to raise some good kids that will leave a good mark on this world."